32
The Nuclear Symmetry Energy and Neutron Star Crusts Lie-Wen Chen ( 陈陈陈 ) (Department of Physics, Shanghai Jiao Tong University) Compact stars in the QCD phase diagram II May 20‐24, 2009 , Beijing laborators -Zhou Jiang (South-East U.) Ming Ko and Jun Xu (TAMU) -An Li (TAMU-Commerce -Chan Yong (IMP,CAS) g-Ru Ma (SJTU) -Gang Xiao and Ming Zhang (Tsinghua U.)

The Nuclear Symmetry Energy and Neutron Star Crusts

Embed Size (px)

DESCRIPTION

The Nuclear Symmetry Energy and Neutron Star Crusts. Collaborators : Wei-Zhou Jiang (South-East U.) Che Ming Ko and Jun Xu (TAMU) Bao-An Li (TAMU-Commerce) - PowerPoint PPT Presentation

Citation preview

Page 1: The Nuclear Symmetry Energy and Neutron Star Crusts

The Nuclear Symmetry Energy and Neutron Star Crusts

Lie-Wen Chen (陈列文 )

(Department of Physics Shanghai Jiao Tong University)

Compact stars in the QCD phase diagram IIMay 20‐24 2009 Beijing

Collaborators Wei-Zhou Jiang (South-East U)Che Ming Ko and Jun Xu (TAMU)Bao-An Li (TAMU-Commerce) Gao-Chan Yong (IMPCAS)Hong-Ru Ma (SJTU) Zhi-Gang Xiao and Ming Zhang (Tsinghua U)

Outline

EOS of asymmetric nuclear matter and the nuclear symmetry energy

Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

The nuclear symmetry energy and neutron star crusts

Summary and outlook

Main References LW Chen CM Ko BA Li and GC Yong Front Phys China 2(3) 327 (2007)

[arXiv07042340]BA Li LW Chen and CM Ko Phys Rep 464 113-281 (2008) [arXiv08043580]J Xu LW Chen BA Li and HR Ma Phys Rev C 79 035802 (2009) [arXiv08074477]J Xu LW Chen BA Li and HR Ma Astrophys J 697 1549-1568 (2009) [arXiv09012309]

I EOS of Asymmetric Nuclear Matter and the Nuclear Symmetry Energy

Neutron Stars hellip

Structures of Radioactive Nuclei SHE hellip

Isospin Effects in HICrsquos hellip

Many-Body Theory

Many-Body Theory

Transport Theory General Relativity

Nuclear Force

EOS for Asymmetric

Nuclear Matter

Density Dependence of the Nuclear Symmetry Energy

HICrsquos induced by

neutron-rich nuclei

(CSRLanzhouFRIBGSIRIKENhelliphellip)

Most uncertain property of an asymmetric

nuclear matter

What is the isospin dependence of the in-medium nuclear effective interactions

Isospin Physics in medium energy nuclear physics

Radioactive beam facilities are being built around the world

IMP CIAE

Providing new opportunities for both nuclear physics and astrophysics

World status of Rare Isotope Accelerators

Many-Body Approaches to Nuclear Matter EOS

Microscopic Many-Body Approaches Non-relativistic Brueckner-Bethe-Goldstone (BBG) Theory Relativistic Dirac-Brueckner-Hartree-Fock (DBHF) approach Self-consistent Greenrsquos Function (SCGF) Theory Variational Many-Body (VMB) approach helliphellip Effective Field Theory Density Functional Theory (DFT) Chiral Perturbation Theory (ChPT) helliphellip Phenomenological Approaches Relativistic mean-field (RMF) theory Relativistic Hartree-Fock (RHF) Non-relativistic Hartree-Fock (Skyrme-Hartree-Fock) Thomas-Fermi (TF) approximations Phenomenological potential models helliphellip

Equation of State of symmetric nuclear matter is relatively well determined

(1) EOS of symmetric matter around the saturation density ρ0

Giant Monopole Resonance 0

22

0 0 2Incompressibility K =9 ( )

d E

d

K0=231plusmn5 MeVPRL82 691 (1999)Recent resultsK0=240plusmn20 MeVG Colo et al U Garg et al

__

GMR 0Frequency f K

(2) EOS of symmetric matter for 1ρ0lt ρ lt 3ρ0 from K+ production in HICrsquosJ Aichelin and CM Ko

PRL55 (1985) 2661C Fuchs

Prog Part Nucl Phys 56 (2006) 1

Transport calculations indicate that ldquoresults for the K+ excitation function in Au + Au over C + C reactions as measured by the KaoS Collaboration strongly support the scenariowith a soft EOSrdquo

C Fuchs et al PRL86 (2001) 1974

Equation of State of symmetric nuclear matter is relatively well determined

See also C Hartnack H Oeschler and J Aichelin

PRL96 012302 (2006)

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 2: The Nuclear Symmetry Energy and Neutron Star Crusts

Outline

EOS of asymmetric nuclear matter and the nuclear symmetry energy

Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

The nuclear symmetry energy and neutron star crusts

Summary and outlook

Main References LW Chen CM Ko BA Li and GC Yong Front Phys China 2(3) 327 (2007)

[arXiv07042340]BA Li LW Chen and CM Ko Phys Rep 464 113-281 (2008) [arXiv08043580]J Xu LW Chen BA Li and HR Ma Phys Rev C 79 035802 (2009) [arXiv08074477]J Xu LW Chen BA Li and HR Ma Astrophys J 697 1549-1568 (2009) [arXiv09012309]

I EOS of Asymmetric Nuclear Matter and the Nuclear Symmetry Energy

Neutron Stars hellip

Structures of Radioactive Nuclei SHE hellip

Isospin Effects in HICrsquos hellip

Many-Body Theory

Many-Body Theory

Transport Theory General Relativity

Nuclear Force

EOS for Asymmetric

Nuclear Matter

Density Dependence of the Nuclear Symmetry Energy

HICrsquos induced by

neutron-rich nuclei

(CSRLanzhouFRIBGSIRIKENhelliphellip)

Most uncertain property of an asymmetric

nuclear matter

What is the isospin dependence of the in-medium nuclear effective interactions

Isospin Physics in medium energy nuclear physics

Radioactive beam facilities are being built around the world

IMP CIAE

Providing new opportunities for both nuclear physics and astrophysics

World status of Rare Isotope Accelerators

Many-Body Approaches to Nuclear Matter EOS

Microscopic Many-Body Approaches Non-relativistic Brueckner-Bethe-Goldstone (BBG) Theory Relativistic Dirac-Brueckner-Hartree-Fock (DBHF) approach Self-consistent Greenrsquos Function (SCGF) Theory Variational Many-Body (VMB) approach helliphellip Effective Field Theory Density Functional Theory (DFT) Chiral Perturbation Theory (ChPT) helliphellip Phenomenological Approaches Relativistic mean-field (RMF) theory Relativistic Hartree-Fock (RHF) Non-relativistic Hartree-Fock (Skyrme-Hartree-Fock) Thomas-Fermi (TF) approximations Phenomenological potential models helliphellip

Equation of State of symmetric nuclear matter is relatively well determined

(1) EOS of symmetric matter around the saturation density ρ0

Giant Monopole Resonance 0

22

0 0 2Incompressibility K =9 ( )

d E

d

K0=231plusmn5 MeVPRL82 691 (1999)Recent resultsK0=240plusmn20 MeVG Colo et al U Garg et al

__

GMR 0Frequency f K

(2) EOS of symmetric matter for 1ρ0lt ρ lt 3ρ0 from K+ production in HICrsquosJ Aichelin and CM Ko

PRL55 (1985) 2661C Fuchs

Prog Part Nucl Phys 56 (2006) 1

Transport calculations indicate that ldquoresults for the K+ excitation function in Au + Au over C + C reactions as measured by the KaoS Collaboration strongly support the scenariowith a soft EOSrdquo

C Fuchs et al PRL86 (2001) 1974

Equation of State of symmetric nuclear matter is relatively well determined

See also C Hartnack H Oeschler and J Aichelin

PRL96 012302 (2006)

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 3: The Nuclear Symmetry Energy and Neutron Star Crusts

I EOS of Asymmetric Nuclear Matter and the Nuclear Symmetry Energy

Neutron Stars hellip

Structures of Radioactive Nuclei SHE hellip

Isospin Effects in HICrsquos hellip

Many-Body Theory

Many-Body Theory

Transport Theory General Relativity

Nuclear Force

EOS for Asymmetric

Nuclear Matter

Density Dependence of the Nuclear Symmetry Energy

HICrsquos induced by

neutron-rich nuclei

(CSRLanzhouFRIBGSIRIKENhelliphellip)

Most uncertain property of an asymmetric

nuclear matter

What is the isospin dependence of the in-medium nuclear effective interactions

Isospin Physics in medium energy nuclear physics

Radioactive beam facilities are being built around the world

IMP CIAE

Providing new opportunities for both nuclear physics and astrophysics

World status of Rare Isotope Accelerators

Many-Body Approaches to Nuclear Matter EOS

Microscopic Many-Body Approaches Non-relativistic Brueckner-Bethe-Goldstone (BBG) Theory Relativistic Dirac-Brueckner-Hartree-Fock (DBHF) approach Self-consistent Greenrsquos Function (SCGF) Theory Variational Many-Body (VMB) approach helliphellip Effective Field Theory Density Functional Theory (DFT) Chiral Perturbation Theory (ChPT) helliphellip Phenomenological Approaches Relativistic mean-field (RMF) theory Relativistic Hartree-Fock (RHF) Non-relativistic Hartree-Fock (Skyrme-Hartree-Fock) Thomas-Fermi (TF) approximations Phenomenological potential models helliphellip

Equation of State of symmetric nuclear matter is relatively well determined

(1) EOS of symmetric matter around the saturation density ρ0

Giant Monopole Resonance 0

22

0 0 2Incompressibility K =9 ( )

d E

d

K0=231plusmn5 MeVPRL82 691 (1999)Recent resultsK0=240plusmn20 MeVG Colo et al U Garg et al

__

GMR 0Frequency f K

(2) EOS of symmetric matter for 1ρ0lt ρ lt 3ρ0 from K+ production in HICrsquosJ Aichelin and CM Ko

PRL55 (1985) 2661C Fuchs

Prog Part Nucl Phys 56 (2006) 1

Transport calculations indicate that ldquoresults for the K+ excitation function in Au + Au over C + C reactions as measured by the KaoS Collaboration strongly support the scenariowith a soft EOSrdquo

C Fuchs et al PRL86 (2001) 1974

Equation of State of symmetric nuclear matter is relatively well determined

See also C Hartnack H Oeschler and J Aichelin

PRL96 012302 (2006)

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 4: The Nuclear Symmetry Energy and Neutron Star Crusts

Radioactive beam facilities are being built around the world

IMP CIAE

Providing new opportunities for both nuclear physics and astrophysics

World status of Rare Isotope Accelerators

Many-Body Approaches to Nuclear Matter EOS

Microscopic Many-Body Approaches Non-relativistic Brueckner-Bethe-Goldstone (BBG) Theory Relativistic Dirac-Brueckner-Hartree-Fock (DBHF) approach Self-consistent Greenrsquos Function (SCGF) Theory Variational Many-Body (VMB) approach helliphellip Effective Field Theory Density Functional Theory (DFT) Chiral Perturbation Theory (ChPT) helliphellip Phenomenological Approaches Relativistic mean-field (RMF) theory Relativistic Hartree-Fock (RHF) Non-relativistic Hartree-Fock (Skyrme-Hartree-Fock) Thomas-Fermi (TF) approximations Phenomenological potential models helliphellip

Equation of State of symmetric nuclear matter is relatively well determined

(1) EOS of symmetric matter around the saturation density ρ0

Giant Monopole Resonance 0

22

0 0 2Incompressibility K =9 ( )

d E

d

K0=231plusmn5 MeVPRL82 691 (1999)Recent resultsK0=240plusmn20 MeVG Colo et al U Garg et al

__

GMR 0Frequency f K

(2) EOS of symmetric matter for 1ρ0lt ρ lt 3ρ0 from K+ production in HICrsquosJ Aichelin and CM Ko

PRL55 (1985) 2661C Fuchs

Prog Part Nucl Phys 56 (2006) 1

Transport calculations indicate that ldquoresults for the K+ excitation function in Au + Au over C + C reactions as measured by the KaoS Collaboration strongly support the scenariowith a soft EOSrdquo

C Fuchs et al PRL86 (2001) 1974

Equation of State of symmetric nuclear matter is relatively well determined

See also C Hartnack H Oeschler and J Aichelin

PRL96 012302 (2006)

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 5: The Nuclear Symmetry Energy and Neutron Star Crusts

Many-Body Approaches to Nuclear Matter EOS

Microscopic Many-Body Approaches Non-relativistic Brueckner-Bethe-Goldstone (BBG) Theory Relativistic Dirac-Brueckner-Hartree-Fock (DBHF) approach Self-consistent Greenrsquos Function (SCGF) Theory Variational Many-Body (VMB) approach helliphellip Effective Field Theory Density Functional Theory (DFT) Chiral Perturbation Theory (ChPT) helliphellip Phenomenological Approaches Relativistic mean-field (RMF) theory Relativistic Hartree-Fock (RHF) Non-relativistic Hartree-Fock (Skyrme-Hartree-Fock) Thomas-Fermi (TF) approximations Phenomenological potential models helliphellip

Equation of State of symmetric nuclear matter is relatively well determined

(1) EOS of symmetric matter around the saturation density ρ0

Giant Monopole Resonance 0

22

0 0 2Incompressibility K =9 ( )

d E

d

K0=231plusmn5 MeVPRL82 691 (1999)Recent resultsK0=240plusmn20 MeVG Colo et al U Garg et al

__

GMR 0Frequency f K

(2) EOS of symmetric matter for 1ρ0lt ρ lt 3ρ0 from K+ production in HICrsquosJ Aichelin and CM Ko

PRL55 (1985) 2661C Fuchs

Prog Part Nucl Phys 56 (2006) 1

Transport calculations indicate that ldquoresults for the K+ excitation function in Au + Au over C + C reactions as measured by the KaoS Collaboration strongly support the scenariowith a soft EOSrdquo

C Fuchs et al PRL86 (2001) 1974

Equation of State of symmetric nuclear matter is relatively well determined

See also C Hartnack H Oeschler and J Aichelin

PRL96 012302 (2006)

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 6: The Nuclear Symmetry Energy and Neutron Star Crusts

Equation of State of symmetric nuclear matter is relatively well determined

(1) EOS of symmetric matter around the saturation density ρ0

Giant Monopole Resonance 0

22

0 0 2Incompressibility K =9 ( )

d E

d

K0=231plusmn5 MeVPRL82 691 (1999)Recent resultsK0=240plusmn20 MeVG Colo et al U Garg et al

__

GMR 0Frequency f K

(2) EOS of symmetric matter for 1ρ0lt ρ lt 3ρ0 from K+ production in HICrsquosJ Aichelin and CM Ko

PRL55 (1985) 2661C Fuchs

Prog Part Nucl Phys 56 (2006) 1

Transport calculations indicate that ldquoresults for the K+ excitation function in Au + Au over C + C reactions as measured by the KaoS Collaboration strongly support the scenariowith a soft EOSrdquo

C Fuchs et al PRL86 (2001) 1974

Equation of State of symmetric nuclear matter is relatively well determined

See also C Hartnack H Oeschler and J Aichelin

PRL96 012302 (2006)

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 7: The Nuclear Symmetry Energy and Neutron Star Crusts

(2) EOS of symmetric matter for 1ρ0lt ρ lt 3ρ0 from K+ production in HICrsquosJ Aichelin and CM Ko

PRL55 (1985) 2661C Fuchs

Prog Part Nucl Phys 56 (2006) 1

Transport calculations indicate that ldquoresults for the K+ excitation function in Au + Au over C + C reactions as measured by the KaoS Collaboration strongly support the scenariowith a soft EOSrdquo

C Fuchs et al PRL86 (2001) 1974

Equation of State of symmetric nuclear matter is relatively well determined

See also C Hartnack H Oeschler and J Aichelin

PRL96 012302 (2006)

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 8: The Nuclear Symmetry Energy and Neutron Star Crusts

(3) Present constraints on the EOS of symmetric nuclear matter for 2ρ0lt ρ lt 5ρ0 using flow data from BEVALAC SISGSI and AGS

Use constrained mean fields to predict the EOS for symmetric matter

bull Width of pressure domain reflects uncertainties in comparison and of

assumed momentum dependence

P Danielewicz R Lacey and WG Lynch Science 298 1592 (2002)

2Pressure P( )s

E

The highest pressure recorded under laboratory controlled conditions in nucleus-nucleus collisions

y

px

High density nuclear matter2 to 5ρ0

Equation of State of symmetric nuclear matter is relatively well determined

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 9: The Nuclear Symmetry Energy and Neutron Star Crusts

Liquid-drop model

Symmetry energy term

W D Myers WJ Swiatecki P Danielewicz P Van Isacker A E L Dieperinkhelliphellip

Symmetry energy including surface diffusion effects (ys=SvSs)

The Nuclear Symmetry Energy

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 10: The Nuclear Symmetry Energy and Neutron Star Crusts

EOS of Asymmetric Nuclear Matter

s2 4

ym ( )( ) ( ) ( )0) ( n pE OE E (Parabolic law)

The Nuclear Symmetry Energy2

sym 2

1 ( )( )

2

EE

The Nuclear Matter Symmetry Energy

0

sym

sy

2

0 0

0 0

s

sy

0

msym 0

0

0

y

m

m

( )3 18

30 MeV (LD mass formula )

( )3 (Many-Body Theory

( )

Exp

( )

50 200 e )M

( )

V

E Myers amp Swiatecki NPA81 Pomorski amp Du

EL

KL

dek PRC67

L

K

E E

0

2sym2

0 sym2

asy sym

sym

(Sharma et al

isobaric incompressiblity

( )9 (Many-Body Theory Exp )

The isospin part of the of asymmetric nuclear matter

700 466 MeV

320 180 6 GMR( M eV

K

K K K

K

L

E

ShlomoampYoungbloodPRC47529(93)

PRC38 2562 (88))

566 1350 34 159 M eV

550 1

(

(T Li et al PRL99162503(2007))00 MeV )

Symmetry energy termSymmetric Nuclear Matter

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 11: The Nuclear Symmetry Energy and Neutron Star Crusts

ChenKoLi PRC72 064309(2005) ChenKoLi PRC76 054316(2007)

The Nuclear matter symmetry energy

ZH Li et al PRC74 047304(2006) Dieperink et al PRC68 064307(2003)

BHF

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 12: The Nuclear Symmetry Energy and Neutron Star Crusts

II Constraining the density dependence of the nuclear symmetry energy in heavy-ion collisions

Promising Probes of the Esym(ρ) in Nuclear Reactions (an incomplete list )

At sub-saturation densities (亚饱和密度行为) Sizes of n-skins of unstable nuclei from total reaction cross sections Proton-nucleus elastic scattering in inverse kinematics Parity violating electron scattering studies of the n-skin in 208Pb np ratio of FAST pre-equilibrium nucleons Isospin fractionation and isoscaling in nuclear multifragmentation Isospin diffusiontransport Neutron-proton differential flow Neutron-proton correlation functions at low relative momenta t3He ratio Hard photon production

Towards high densities reachable at CSRChina FAIRGSI RIKEN GANIL and FRIB (高密度行为) π -π + ratio K+K0 ratio Neutron-proton differential transverse flow np ratio at mid-rapidity Nucleon elliptical flow at high transverse momenta np ratio of squeeze-out emission

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 13: The Nuclear Symmetry Energy and Neutron Star Crusts

Solve the Boltzmann equation using test particle method Isospin-dependent initialization Isospin- (momentum-) dependent mean field potential

Isospin-dependent N-N cross sections a Experimental free space N-N cross section σexp

b In-medium N-N cross section from the Dirac-Brueckner approach based on Bonn A potential σin-medium

c Mean-field consistent cross section due to m Isospin-dependent Pauli Blocking

0 sym

1(1 )

2 z CV V V V

Phase-space distributions ( ) satify the Boltzmann equation

( ) ( )p r r p c NN

f r p t

f r p tf f I f

t

Isospin-dependent BUU (IBUU) model

Transport model for HICrsquos

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 14: The Nuclear Symmetry Energy and Neutron Star Crusts

Isospin- and momentum-dependent potential (MDI)

30

0

0

0

016 fm

( ) 16 MeV

MDI Interaction

( ) 316 MeV

211 MeV

06

g( o )

8

G ny

sym

E A

E

K

m m

ChenKoLi PRL94032701

(2005)LiChen PRC72 064611

(2005)

DasDas GuptaGaleLi

PRC67034611 (2003)

Transport model IBUU04

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 15: The Nuclear Symmetry Energy and Neutron Star Crusts

2

NNmedium free

NN

in neutron-rich mattermedium free

NN is the reduced mass of the

colliding pair NN in mediumJW Negele and K Yazaki PRL 47 71 (1981)VR Pandharipande and SC Pieper PRC 45 791 (1992)M Kohno et al PRC 57 3495 (1998)D Persram and C Gale PRC65 064611 (2002)

1 In-medium cross sections are reduced2 nn and pp cross sections are splitted due to the neutron-proton effective

mass slitting in neutron-rich matter

LiChen PRC72 (2005)064611

Medium effects effective mass on the incoming current in initial state and level density of the final state

Neglecting medium effects on the transition matrix

In-medium Nucleon-nucleon cross sectionsEffective mass scaling model

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 16: The Nuclear Symmetry Energy and Neutron Star Crusts

0

0

( ) 316( ) MeV

(From

Fit the symmetry ene

0 ) we obtain

rgy w

1

069 for

0

ith

5 f 1

0

or

sym

x

x

E

(1) Isospin diffusion

(2) Isospin scaling

ChenKoLi PRL94(05) PRC72(05) LiChen PRC72(05)

Shetty et alPRC75(07)PRC76(07)

Zhang et alPLB664(08)

(3) Double np ratio

0( )

with 05

ipotsym

i

E

Symmetry Energy Sub-saturation density behaviors

IBUU04

ImQMD

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 17: The Nuclear Symmetry Energy and Neutron Star Crusts

IBUU04 S~316(o)

ImQMD Double np ratios and two isospin diffusion measurements

Consistent constraints from the 2 analysis of three observables

S=125(o)23 + 176 (o)

i

i

i

i i

TsangZhangDanielewiczFamianoLiLynchSteiner PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 18: The Nuclear Symmetry Energy and Neutron Star Crusts

105

00

069 316( 316( ) )( )

Symmetry energy constrained at -saturation densities

between the and lines agrees extremely well with the

sub

-1 0 PR

AsymE

x x

(IBUU04)

(ImQMD)

X=-1

ChenKoLi PRL 94 032701 (2005) Tsang et al PRL 102 122701 (2009)

Symmetry Energy Sub-saturation density behaviors

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 19: The Nuclear Symmetry Energy and Neutron Star Crusts

Subthreshold K0K+ yield may be a sensitive probe of the symmetry energy at high densities

AichelinKo PRL55 2661 (1985) Subthreshold kaon yield is a sensitive probe of the EOS of nuclear matter at high densities (ZX Li QF Li et al M Di Toro et al hellip)

Theory Famiano et al PRL97 052701 (2006)Exp Lopez et al FOPI PRC75 011901(R) (2007)

96 9644 44

96 9640 40

Ru+ Ru and

Zr+ Zr1528 AGeV

K0K+ yield is not so sensitive to the symmetry energy Lower energy and more neutron-rich system

High density behaviors Kaon Probe

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 20: The Nuclear Symmetry Energy and Neutron Star Crusts

IBUU04 XiaoLiChenYongZhang PRL102 062502(2009) A Quite Soft Esym at supra-saturation densities

M Zhang et al arXiv09040447

High density behaviors Pion Probe

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 21: The Nuclear Symmetry Energy and Neutron Star Crusts

LattimerPrakash Science 304 536 (2004)

Neutron star has solid crust over liquid coreRotational glitches small changes in period from sudden unpinning of superfluid vortices Evidence for solid crust 14 of Vela moment of

inertia glitches Needs to know the

transition density to calculate the fractional moment of inertia of the crustLink et al PRL833362 (99)

III The Nuclear Symmetry Energy and Neutron Star Crusts

core-crust transition

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 22: The Nuclear Symmetry Energy and Neutron Star Crusts

2 Thermodynamic approach

Or similarly one can use 3 the RPA

If one uses the parabolic approximation (PA)

Then the stability condition is

gt0

Onset of instability in the uniform n+p+e matter

1 Dynamical approachk0 (neglecting Coul)

Stability condition

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 23: The Nuclear Symmetry Energy and Neutron Star Crusts

Core-Crust Transition Density Parabolic Law fails

(1) It is NOT enough to know the symmetry energy one almost has to know the exact EOS of n-rich matter

WhyBecause it is the determinant of the curvature matrixthat determines the stability condition Example

Not so surprise

ZhangChen CPL 18 (2000) 142Steiner PhysRev C74 (2006) 045808

Higher-order term effects on direct URCA

XuChenLiMa PRC79 035802 (2009)

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 24: The Nuclear Symmetry Energy and Neutron Star Crusts

(2) Locating the inner edge of neutron star crust

Kazuhiro Oyamatsu Kei Iida

Phys Rev C75 (2007) 015801

pasta

XuChenLiMa PRC79 035802 (2009)

XuChenLiMa ApJ 697 1547 (2009) arXiv09012309

Parabolic Approximation has been assumed

Significantly less than their fiducial valuesρ t=007-008 fm-3 and Pt=065 MeVfm3

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 25: The Nuclear Symmetry Energy and Neutron Star Crusts

(3) Constraints on M-R relation of NS

(Isospin Diff)

(Empirical estimate Link et al PRL833362(99))

LattimerPrakash

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 26: The Nuclear Symmetry Energy and Neutron Star Crusts

(4) Properties of neutron star crusts

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

Larger L leads to thicker neutron-skin but thinner neutron star crust

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 27: The Nuclear Symmetry Energy and Neutron Star Crusts

(5) Inner Crust EOS Dependence

XuChenLiMa ApJ 697 1549 (2009) arXiv09012309

The mass is insensitive to the inner crust EOSThe radius is sensitive to the inner crust EOS for a softer symmetry energyThe inner crust EOS has tiny effects on the dII when dII is small

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 28: The Nuclear Symmetry Energy and Neutron Star Crusts

The softest symmetry energythat the TOV is still stable is x=093 giving M_max=011 solar mass and R=gt28 km

For pure nucleonic matterNew PhysicsSoft symmetry energy at HD

K0=211 MeV is used higher incompressibility

for symmetric matter will lead to higher masses systematically

(6) HD Esym and properties of neutron stars

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 29: The Nuclear Symmetry Energy and Neutron Star Crusts

The isospin diffusion data Isoscaling and Isotope dependence of GMR seem to give a stringent constraint for the sub-saturation density behavior of the symmetry energy (L=86plusmn25 MeV and Kasy=-500plusmn50 MeV)

Probing the high density behavior of the symmetry energy remains a big challenge and the pion ratio data from FOPI favor a quite soft Esym at high densities

Significant constraints on inner edge and crust properties of neutron stars have been already obtained from present knowledge on symmetry energy at sub-saturation density region

Crosscheck is definitely needed

IV Summary and Outlook

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 30: The Nuclear Symmetry Energy and Neutron Star Crusts

Thanks

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 31: The Nuclear Symmetry Energy and Neutron Star Crusts

Institute of Nuclear Particle Astronomy and Cosmology-INPAC Shanghai Jiao Tong University

httpphysicssjtueducniwdd09indexhtml

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30
Page 32: The Nuclear Symmetry Energy and Neutron Star Crusts

International workshop on nuclear dynamics in heavy-ion reactionsand the symmetry energy (IWND2009)

August 22ndash25 Shanghai China

OrganizersShanghai Institute of Applied Physics CAS

Shanghai Jiao Tong UniversityBeijing Normal University

Institute of Modern Physics CAS

  • Slide 1
  • Slide 30