Hot and dense matter in neutron stars and core-collapse supernovae

Hot and dense matter in neutron stars andcore-collapse supernovae

Micaela [email protected]

Laboratoire Univers et Theories (LUTH)CNRS / Observatoire de Paris/ Universite Paris Diderot

Les grandes questions en physique nucleaire fondamentale, June 21 - 22, 2016

Micaela Oertel (LUTH) Matter in NS/CCSN Paris, June 21st, 2016 1 / 14

http://luth.obspm.fr

Outline

1 Some general remarks

2 What do we know?

3 Open problemsClusterised matterHomogeneous matterWhat about “exotic” matter ?

4 Summary


Outline


2 What do we know?


4 Summary


Outline


2 What do we know?


4 Summary


Outline


2 What do we know?


4 Summary


Why are we interested in hot and densematter ?

Astrophysical point of view :

Supernovae/hypernovae (stellar evolution,explosion mechanism, formation of compactobjects,. . .)

Compact object mergers (gravitationalwaves, γ-ray bursts, . . .)

Site for production of heavy elements andchemical evolution of the universe

→ see talks this afternoon

Crab nebula (Hubble telescope)

Microphysics point of view :

Neutrino interactions (with matter and neutrino oscillations)

Study (strongly interacting) matter under extreme conditions of temperatureand density not reachable in terrestrial experiments


What is “hot and dense” ?We want to describe :

Core-collapse supernovae and subsequent neutron star/black hole formationBinary neutron star mergers and neutron star black hole mergersNeutron stars

→ Large domains in density, temperature and asymetry have to be covered

temperature 0 MeV ≤ T < 150 MeVbaryon number density 10−11 fm−3 < nB < 10 fm−3

electron fraction 0 < Ye < 0.6

and matter composition changes dramatically throughout !

Different regimes :Very low densities and temperatures :

I dilute gas of non-interacting nuclei → nuclear statistical equilibrium (NSE)

Intermediate densities and low temperatures :I gas of interacting nuclei surrounded by free nucleons → beyond NSE

High densities and temperatures :I nuclei dissolve

→ strongly interacting (homogeneous) hadronic matterI potentially transition to the quark gluon plasma


Constraints on the EoS1. Constraints related to nuclear experiments and theoretical developments

Extracting parameters ofsymmetric nuclear matteraround saturation(n0, EB ,K, J, L)

Data from heavy ion collisions(flow constraint, mesonproduction, . . .)

Data on nucleon-nucleoninteraction fixing startpoint ofmany-body calculations (dataon hyperonic interactions scarce→ talk by E. Khan)

Low density neutron matter :Monte-Carlo simulations andEFT approaches

Distribution of values for J and L

20 22 24 26 28 30 32 34 36 38 40 42 44symmetry energy at saturation J [MeV]

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

pro

bab

ilit

y d

P/d

J [M

eV-1

]

(31.7 +/- 3.2) MeV

J =

0 10 20 30 40 50 60 70 80 90 100 110 120symmetry energy slope coefficient L [MeV]

0.00

0.02

0.04

0.06

0.08

0.10

pro

bab

ilit

y d

P/d

L [

MeV

-1] L =

(58.7 +/- 28.1) MeV

[MO, M. Hempel, T. Klahn, S. Typel 2016]


Constraints on the EoS2. Constraints from astrophysical observations

Observed masses in binary systems (NS-NS,NS-WD, X-ray binaries) with most precisemeasurements from double neutron starsystems.

Many NS-NS systems give masses close to1.4M�Two precise mass measurements in NS-WDbinaries

I M = 1.928± 0.017M� (PSR J1614-2230)[Demorest et al 2010, Fonesca et al 2016]

I M = 2.01± 0.04M� (PSR J0348+0432)[Antoniadis et al 2013]

0.5 1 1.5 2 2.5 3 3.5

MG [Msol]

4U 1700-377B1957+204U 1822-371Vela X-1Cyg X-2EXO 1722-363XTE J2123-058Cen X-3IGR J18027-2016OAO 1657-4152S 0921-630LMC X-4Her X-1SMC X-14U 1538-52J1816+4510J1311-3430CompanionJ1829+2456CompanionJ1811-1736CompanionJ1906+0746CompanionB1534+12CompanionB1913+16CompanionB2127+11CJ0737-3039BJ0737-3039ACompanionJ1756-2251CompanionJ1807-2500BCompanionJ0453+1559B12303+46J1713+0747B1855+09J1748-2446JJ0024-7204HJ0514-4002AB1802-07J0621+1002J1748-2446IJ1909-3744J1738+0333J1853+1303J1750-37AJ2106+1948J2019+2425J1045-4509J2043+1711B1911-5958AJ1804-2718J1910+1256J1614-2230J1748-2021BJ0751+1807J1141-6545J1012+5307J0437-4715B1802-2124B1516+02BJ0348+0432J0045-7319J1903+0327

NS-NS binaries

WD-NS binaries

X-ray/optical binaries

NS-Main Sequence binaries

[Update from Lattimer & Prakash, 1012.3208]

2 M� perhaps not the end of the story (e.g. indications for a 2.4 M� NS inB1957+20 (van Kerkwijk et al., ApJ 2011))


Constraints on the EoS

3. Other NS observations

Measurements of rotational frequencyI f = 716 Hz (PSR J1748-2446ad)

(Hessels et al, Science 2006)

I f = 1122 Hz not confirmed ! (XTEJ1739-285) (Kaaret et al. ApJ 2007)

Theory : Kepler frequency fK =1008Hz (M/M�)1/2 (R/10km)−3/2

(Haensel et al. A&A 2009)

→ A measured frequency of 1.4 kHzwould constrain R1.4 < 9.5 km !

APR

FPS

DH

BGN1H1

GMGS

BM165

SQM3 SQM1

(Courtesy of M. Fortin, CAMK)

Radius determinations so far model dependent (atmosphere model, distance,. . .)

Moment of inertia, asteroseismology, . . .model dependent, too → nostringent constraint so far


Clustered matterNuclear abundances important for composition of (proto-)neutron star crust,nucleosynthesis and CCSN matterModelling does not only depend on the interaction chosen :

Theoretical description of inhomogeneous system (interplay of Coulomb andstrong interaction, surface effects, . . .)

Binding energies of (neutron rich) nuclei

Treatment of excited states

Transition to homogeneous matter (stellar matter is electrically neutral !)

Nuclear abundances within different models (same thermodynamic conditions, gas density negligible)

0

10

20

30

40

50

60

70

Z

0 10 20 30 40 50 60 70 80 90 100 110 120

N

log10(XN,Z)

-10-8-6-4-20

a) SMSM

nB = 5.69 10-4

fm-3

T = 1.60 MeV

Ye = 0.35

0

10

20

30

40

50

60

70

Z

0 10 20 30 40 50 60 70 80 90 100 110 120

N

log10(XN,Z)

-10-8-6-4-20

b) Gulminelli and Raduta (2015)

0

10

20

30

40

50

60

70

Z0 10 20 30 40 50 60 70 80 90 100 110 120

N

HS(DD2)

STOS

LS220

log10(XN,Z)

-10-8-6-4-20

c) HS(DD2)


Reaction rates

Overall reaction rates : matter composition + individual ratesI Homogeneous matter : calculate individual rates in hot and dense medium

→ collective responseI Clustered matter : rates on nuclei far from stability (up to now essentially shell

model)

Different (weak) interactionrates are extremely important !Neutrino emission, electroncapture, . . .

And very sensitive to thedifferent ingredients

I Example : influence ofnuclear masses for nuclei withneutron numbers betweenN = 50 and N = 82→ up to 30% change inoverall EC rate

Nuclear masses and EC rates

-0.2

-0.1

-0

0.1

0.2

0.3

10-6

10-5

10-4

10-3

∆Z=2 25Msun

∆Z=2 15Msun

∆Z=5 25Msun

∆Z=5 15Msun

∆Z=10 25Msun

∆Z=10 15Msun

nB (fm

-3)

< λ

ecm

> / <

λec >

- 1

0

0.5

10-4

10-3

[Raduta et al 2016]


Neutron matter and M-R relationComparison of different NM calculations

0

5

10

15

20

25

30

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18

E/A

(M

eV

)

nB (fm-3

)

AFQMC (AV + TBF)AFQMC (2NF)

AFQMC (2NF + 3NF)APR

Friedman-PandharipandeHebeler et al. (2010)

χPT, Fiorilla et al. (2012)BHF (AV + TBF)

Pure neutron matter well suited forab-initio calculations

For nB <∼ 0.16 fm−3, all ab-initiocalculations in reasonable agreement

Uncertainties mainly due to 3N forces

Constraints on NS M -R relation fromBPS crust (nB < n0/2) + NM +polytropes

But at low M radii very sensitive tocrust-core matching and treatment ofthe crust [M. Fortin et al. 2016]

Development of ’generic’ parameterisedEoS

Combination of NM results + Mmax = 1.97M�

8 10 12 14 160

0.5

1

1.5

2

2.5

3

causality

Radius [km]M

ass[M

�]

[Hebeler et al., 2013]


The hyperon puzzle1. The problem

Most models predict hyperons at nB >∼ 2− 3n0 but give maximum neutronstar masses of ∼ 1.4M� → need short-range repulsion to stiffen the EoS

2. Different solutions

Let quark matter appear early (very early !) enough :Phenomenological quark models can be supplemented with the necessaryrepulsion [Weissenborn et al., ’11, Alford et al. ’07,. . .]

Modify the interactionI In microscopic models (BHF) this seems to

be a problem [Vidana et al., ’11, Schulze & Rijken ’11]

I In phenomenological models not difficult[Bednarek et al. ’12, Bonanno & Sedrakian ’12,Weissenborn et al. ’12, MO

et al. ’12,. . .], high density repulsion mainly viaY Y interaction

Different hyperonic interactions

0

0.5

1

1.5

2

2.5

10 11 12 13 14 15 16

LS220Λ

LS220

LS220π

STOSY

STOSΛ

STOSYπ

STOS

BHBΛ

HS(DD2)

BHBΛφ

DDHδ Y4

DDHδ

GM1 Y6

GM1

TM1-2 (110)

TM1-2 (55)

TM1-2 Λ4

TM1-2 Λ6

TM1-2 Y1TM1-2 Y2R (km)

M (

Mso

l)

[MO, C. Providencia, F. Gulminelli, A. Raduta 2015]

Large variety in different radii and strangeness contents


More remarks on ’exotics’Phase diagram of baryonic matter with strangeness

0

0.05

0.1

0.15

0.2

0.25

0.3 0.4 0.5 0.6 0.7 0.8 0.9

nB (fm

-3)

nL (

fm-3

)

[MO, F. Gulminelli, C. Providencia, A. Raduta, 2016]

Is the onset of hyperonic degrees offreedom accompanied by a phasetransition ?

If yes, many interesting effects :neutrino mean free path . . .

Model and interaction dependent

Temperature effects in favor ofnon-nucleonic degrees of freedom

What about nuclear resonances,mesons, muons ?

Is there a transition to the QGP ?

Strangeness fraction > 10−4

0

5

10

15

20

25

30

35

40

45

50

T(M

eV

)10

-610

-510

-410

-310

-210

-11

nB (fm-3

)

Yq 0.5

LS220

BHB

STOS

STOSY

[MO, M. Hempel, T. Klahn. S. Typel, 2016]


Conclusion

We need to know matter properties (EoS and reaction rates) in regions notaccesible to experiments !

1. Many open questions :

1 How and under which conditions do non-nucleonic degrees of freedomappear ?

2 When does nuclear matter deconfine ?

3 Can we develop a QCD based framework that covers the relevant range ofvariables ?

4 How to better treat spatially inhomogeneous matter and cluster formation ?

5 How to describe phase transitions consistently ?


Idea of the CompOSE project withinNewCompstar

Provide data tables for different EoS ready for further use in astrophysics ofcompact objects and nuclear physics (core team : S. Typel, T. Klahn, MO) :

http ://compose.obspm.fr

CompOSE is a repository of EoS tables in a common format for direct usagewith information on a large number of thermodynamic properties, on thechemical composition of dense matter and, if available, on microphysicalquantities of the constituents.

CompOSE allows to interpolate the provided tables using different schemesto obtain the relevant quantities, selected by the user, for grids that aretailored to specific applications.

CompOSE can provide information on additional thermodynamic quantities,which are not stored in the original data tables, and on further quantities,which characterize an EoS such as nuclear matter parameters and compactstar properties.


Documents

Hot and dense matter in neutron stars and core-collapse supernovae