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24 - 26th November 2008 1CEA / DIF Workshop Pulsars
Microscopic data and supernovae evolution
Patrick Blottiau( CEA / DIF )
Anthea Fantina, Elias Khan, Jérôme Margueron ( IPN Orsay )Philip Mellor ( CEA / DIF )Pierre Pizzochero ( Università degli Studi di Milano )Jérôme Novak, Micaela Oertel ( LUTH Meudon )
Karim Hasnaoui ( GANIL Caen )Jesús Navarro ( IFIC Universidad de Valencia )
Camille Ducoin ( LPC Caen )Francesca Gulminelli ( LPC Caen )
24 - 26th November 2008 2CEA / DIF Workshop Pulsars
Summary
• Prompt explosion mechanism → delayed neutrino-driven scenario
• 2D and 3D hydro codes -> convection, instabilities, mixing, rotation
• Refined neutrino transport schemes
• New ingredients : General Relativity, Magneto Hydrodynamics
• Standing Accretion Shock Instability model
• New data in microscopic physics : nuclear EOS, electron capture rates,ν mean free paths (RPA)
• Shock energy impact on the outgoing shock of the supernova
24 - 26th November 2008 3CEA / DIF Workshop Pulsars
Stellar evolution according to the initial mass ( Harvard – CFA )
24 - 26th November 2008 4CEA / DIF Workshop Pulsars
15 M0 and 25 M0 presupernovae ( Heger et al., 2002 )
24 - 26th November 2008 5CEA / DIF Workshop Pulsars
Standard Scenario (1)
• Onion skin structure ( M > 8 M0 ) with an iron core
• Gravitational instability : nuclear photodissociation and electron capture
• Adiabatic core collapse ( S / kN ≈ 1 ) with an homologous central zone evolution
• Neutrino trapping ( 5 1011 g/cm3 )
• Stiffening of nuclear matter :
Shock wave formation, propagating to the outer layers
24 - 26th November 2008 6CEA / DIF Workshop Pulsars
Standard Scenario (2)
Evolution of a 15 M0 progenitor
24 - 26th November 2008 7CEA / DIF Workshop Pulsars
Standard Scenario (3)
t=0 ms
359.5
360.8
364.4
361.5
362.6
Velo
city
v/
c
t=0 ms
359.5
360.8
364.4
361.5
362.6
Velo
city
v/
c
M / M0
24 - 26th November 2008 8CEA / DIF Workshop Pulsars
Type II supernova new scenario
( H.-Th. Janka, Astron. Astrophys. 368, 527 (2001) )
Role of neutrinos(Colgate et White, 1966)
Prompt explosion(Bethe et al., 1979) BBAL
→Delayed explosion
(Bowers et Wilson, 1982)(Bethe et Wilson, 1985)
→Role of convection
(Wilson et Mayle, 1988)(Herant et al., 1992)
(Burrows et al., 1995) SASI(Blondin, 2003)
Advective-acoustic cycle (Foglizzo, 2001, Foglizzo et al., 2007)Pure acoustic mechanism (Blondin et Mezzacappa, 2006)
→
24 - 26th November 2008 9CEA / DIF Workshop Pulsars
Explosion of 15 M0 rotating star ( Garching group, 2008 )
ν-driven explosion of a rotating 15 M0 ( Marek and Janka, 2008 )
24 - 26th November 2008 10CEA / DIF Workshop Pulsars
Type II supernova hydrocode (1)
Euler equation :
Energy conservation equation :
Electron fraction equation :
EOS :
BBAL, 1979 + Suraud, 1984 ( γ = 1.29 → 2 ) → Lattimer and Swesty, 1991
2
Du u u P GMuDt t r rρ
∂ ∂ ∇= + = − −
∂ ∂
.D P D QuD t D t
ερ
= − ∇ +
1 .
Ne
i c a p t i
D Y d fD t d t
ν
=
⎛ ⎞∝ − ⎜ ⎟⎝ ⎠
∑
24 - 26th November 2008 11CEA / DIF Workshop Pulsars
Type II supernova hydrocode (2)
Electron capture :
Neutrino transport : flux-limited diffusion and N energy groups
Diffusion coefficient :
Thick medium :
Thin medium : free propagation at c
( , ) ( 1, )e
e
e Z A Z Ae p n
νν
−
−
⎧ + → + −⎨
+ → +⎩
( ).
1 1.c a p t i
f d fD fc t c d t
ν νν
∂ ⎛ ⎞= ∇ ∇ + ⎜ ⎟∂ ⎝ ⎠
( Fuller, 1982 and 1985 )
24 - 26th November 2008 12CEA / DIF Workshop Pulsars
Warm and dense matter equation of state
ρ < ρ0 /10 : Total Pressure = Pe + Pion + PradPe,= f(µe, T, Ye) Fermi-Dirac Prad = 1/3 a T4 ( a = 7.565 10-15 C.G.S. )Pion = f(<A>, α, p, n) ( BBAL, 1979 )
W/A = Wvol + Wsur A-1/3+ Wcoul A2/3
Free energy minimization→ <A> = Wsur / 2 Wcoul
Thermal energy of nuclei excited states( Bethe et al., 1983 )
Recent EOS → Lattimer and Swesty, 1991 ; Shen, 1998 ; Rampp and Janka, 2002
ρ > ρ0 /10 : Bonche and Vautherin, 1981 ; Suraud, 1984 ( γ =1.29 → 2 ) ;Gogny D1P
2 *
,0,0
kT) m ( 34 )4 mth F
F
MeVπε εε
2 ( = ≈
24 - 26th November 2008 13CEA / DIF Workshop Pulsars
Electron capture on nuclei and free protons (1)
( )1 1 11c a p t a e
d f f fc d t
νν νλ λ
⎛ ⎞ = − + −⎜ ⎟⎝ ⎠
24 - 26th November 2008 14CEA / DIF Workshop Pulsars
Electron capture on nuclei and free protons (2)
N ≥ 40 et Z ≤ 40 → Allowed Gamow-Teller transitions are stopped ( G.M. Fuller, 1982 )→ capture on free protons + excited nuclear configurations + configurations mixing +
‘’forbidden’’ captures due to neutral currents
Recent calculations ( K. Langanke et al., 2003 ) : capture on nuclei dominates for A > 55
Gamow-Teller transitions dominate for low densities
Forbidden transitions contribute largely for ρ ≥ 1011 g/cm3
Temperature dependence of the effective mass :
( P. Donati, P.M. Pizzochero, P.F. Bortignon, R.A. Broglia, PRL. 72, 2835 (1994))( A. Fantina, thesis, ‘’SNII : weak processes and dynamic of gravitational collapse’’ (2007))
mTmmm k /)(*ω=
24 - 26th November 2008 15CEA / DIF Workshop Pulsars
Temperature dependence of Neutrino Mean Free Paths
( J. Margueron, J. Navarro and N. Van Giai, Nucl. Phys. A 719, 169 (2003) )
24 - 26th November 2008 16CEA / DIF Workshop Pulsars
Nuclear Equation of State and liquid-gas transition (1)
( J. Margueron, J. Navarro and P. B., Phys. Rev. C 70, 028801 (2004) )( C. Ducoin, J. Margueron and Ph. Chomaz, Nucl. Phys. A 809, 30 (2008) )
24 - 26th November 2008 17CEA / DIF Workshop Pulsars
Nuclear Equation of State and liquid-gas transition (2)
( J. Margueron, J. Navarro and P. B., Phys. Rev. C 70, 028801 (2004) )
D1P Gogny effective interaction → Nuclear EOS + HF + RPA → λν
Neutrino trapping in a thin layer :
revival shock ?
24 - 26th November 2008 18CEA / DIF Workshop Pulsars
Nuclear Equation of State and liquid-gas transition (3)
Mean-Field approach, using Sly230a effective interaction + Coulomb frustration Ising Model with long-range Coulomb force and short-range nuclear interaction
Limiting temperature for the extended coexistence phase region of the Neutron StarCoulomb Field : weak opacity for neutrino diffusionA.S. Botvina and I. N. Mishustin : critical point at T = 15 MeV
'
,2 2
V Vi j
N C N C i ji j i j ij
qqH H H nn
rε λε
+≠
= + = +∑ ∑
( C. Ducoin, K. Hasnaoui, P. Napolitani, Ph. Chomaz, F. Gulminelli, PR. C 75, 065805 (2007) )( P. Napolitani, Ph. Chomaz, F. Gulminelli and K. Hasnaoui, PRL. 98, 131102 (2007) )
24 - 26th November 2008 19CEA / DIF Workshop Pulsars
Future prospects
( P. B., J. Margueron and Ph. Mellor, Proc. EXOCT07, Catania (2007) )
1D tool → to test new effects and new dataElectron capture rates (A. Fantina Ph.D.)Neutrino Mean Free Paths (RPA) Nuclear equations of state
Liquid-gas phase transition and spinodal instabilityCritical temperatureNeutrino trapping
Multi-dimensional simulationsPrecise neutrino transport treatmentConvection and instabilities role (SASI)
Other effectsMHD, General Relativity, Rotation …