Spectroscopy in Stellar Astrophysics Alberto Rebassa Mansergas.
Phase diagram of stellar matter and its impact on astrophysics
description
Transcript of Phase diagram of stellar matter and its impact on astrophysics
Francesca Gulminelli - LPC Caen, FranceCollaboration:Adriana Raduta IFIN BucharestMicaela Oertel LUTH Meudon FrancePanagiota Papakonstantinou IPNO FranceJerôme Margueron IPNO France
Phase diagram of stellar matter and its impact on
astrophysics
2/27
A
yp@ 1/2T~1012Kr~r0
Supernova remnant and neutron star in Puppis A (ROSAT x-ray)
yp@ 1/5T~6Kr~r0
corecrust
yp@ 1/3T~1011Kr~r0
Dense matter is abundantly produced in a core-collapse supernova event leading to a neutron star (or black hole)
Time
A.Fantina, PhD thesis, 2011
3/27
Phases of dense matter in neutron stars
Baryon density
G.Watanabe et al, PRL 2009
pasta
QGP?
4/27
2020
0 M
eV
1 5?Density r/r0
Tem
pera
ture
QGP
Gas Liquid
Hadronic matter
Phases of dense matter in heavy-ion collisions
LHC
RHICFAIR
GANIL
5/27
2020
0 M
eV
1 5?Density r/r0
Tem
pera
ture
QGP
Gas Liquid
Hadronic matter
Phases of dense matter in heavy-ion collisions
This talk: Stellar matter versus nuclear matter phase diagram
The sub-saturation regime : Coulomb effects and dishomogeneous phases
The super-saturation regime: Hyperonic matter & strangeness phase transition
T
rBpasta
QGP???
This talk: Stellar matter versus nuclear matter phase diagram
The sub-saturation regime : Coulomb effects and dishomogeneous phases
The super-saturation regime: Hyperonic matter & strangeness phase transition
T
rBpasta
QGP???
G Lcoex
Coulomb effects
Nuclear matter is uncharged, while in stellar matter the proton charge is screened by a ~ uniform electron background
T. Maruyama et al. PRC 72, 015802 (2005)
Den
sité
/ fm
-3
0.080.060.040.02
0
r = 0.04 fm-3 r = 0.08 fm-3r = 0.05 fm-3r = 0.02 fm-3
pne
0 5 10Rayon / fm
0 50 5 100 5 10
Density r/r0
Tem
pera
ture
Nuclear matter is uncharged, while in stellar matter the proton charge is screened by a ~ uniform electron background
The low density phase is a Wigner cristal
Density r/r0
Tem
pera
ture
Coulomb effects
Nuclear matter is uncharged, while in stellar matter the proton charge is screened by a ~ uniform electron background
The low density phase is a Wigner cristal Phase coexistence i.e. macroscopic density dishomogeneities,
would imply a macroscopic charge => a diverging energy density
Coulomb effectsDensity r/r0
Tem
pera
ture
Nuclear matter is uncharged, while in stellar matter the proton charge is screened by a ~ uniform electron background
The low density phase is a Wigner cristal Phase coexistence i.e. macroscopic density dishomogeneities,
would imply a macroscopic charge =>a diverging energy density
Dishomogeneities occur on a microscopic scale only: a continuous transition through a cluster phase (inner crust)
Coulomb effectsDensity r/r0
Tem
pera
ture
Nuclear matter is uncharged, while in stellar matter the proton charge is screened by a ~ uniform electron background
The low density phase is a Wigner cristal Phase coexistence i.e. macroscopic density dishomogeneities,
would imply a macroscopic charge =>a diverging energy density
Dishomogeneities occur on a microscopic scale only: a continuous transition through a cluster phase (inner crust)
Illustration via a phenomenological model
Coulomb effectsDensity r/r0
Tem
pera
ture
The extended NSE model Mixture of nucleons, clusters
of all sizes, photons, electrons, positrons, neutrinos
Nucleons treated in the Skyrme-HF approximation with realistic effective interactions
Nuclei form a statistical ensemble of excited clusters interacting via Coulomb and excluded volume
Thermodynamic consistency between the different components
, , ,p lep e n NT y T Tr =
22
* *ˆ ˆ, , exp
3 3pN n
n n p sp mfn p
V VT h hT m m
=
{ } 4
3/ 2 ,
, ,!
( )2
A
A
Ay p
nA
Nn A A
e yAAy T
A N n AyY A
Tn
m TV V g T e
r r
r
=
=
=
=
,
;
nucleons clusi i
nucleons clus nucleons clusi i i
i n p
P P P
r r r
= =
= =
A.Raduta,F.G.,PRC 82:065801 (2010) PRC 85:025803 (2012)
The extended NSE model A.Raduta,F.G.,PRC 82:065801 (2010) PRC 85:025803 (2012) No plateau in the EoS
B
I=1.6MeVT =1.6 MeV
The extended NSE model A.Raduta,F.G.,PRC 82:065801 (2010) PRC 85:025803 (2012) No plateau in the EoS
Thermodynamics very different from a first order phase transition
Inaccessible in the standard grand-canonical NSE
Large distribution of cluster size
B
S. R. Souza, et al,, Astrophys. J. 707, 1495 (2009),M. Hempel and J. Schaffner-Bielich, Nucl. Phys. A 837, 210 (2010) S. I. Blinnikov, et al, Astronomy & Astrophysics 535, A37 (2011). …………(among others)………
I=1.6MeVT =1.6 MeV
The extended NSE model A.Raduta,F.G.,PRC 82:065801 (2010) PRC 85:025803 (2012) No plateau in the EoS
Thermodynamics very different from a first order phase transition
Inaccessible in the standard grand-canonical NSE
Large distribution of cluster size
The extended NSE model A.Raduta,F.G.,PRC 82:065801 (2010) PRC 85:025803 (2012) No plateau in the EoS
Thermodynamics very different from a first order phase transition
Inaccessible in the standard grand-canonical NSE
Large distribution of cluster size
Important for e-capture and n-dynamics
Towards a quantitative EoS
The nuclear cluster energy functional is modified by the external nucleon gas
Does excluded volume account for this effect ?
M.Hempel et al PRC 84, 055804 (2011)
In medium effects calculated from a HF calculation in the WS cell
Application to the NSE model in progress
P.Papakonstantinou, et al., in preparation
𝑒𝑛𝑢𝑐𝑙 (𝐴 ,δ )= (𝑎𝑉𝑚(𝜌)+𝑎𝑠𝑦𝑚
𝑚 (𝜌)𝛿2 ) 𝐴+(𝑎𝑠𝑦𝑚
𝑚 (𝜌 )+𝑎𝑠𝑑𝑚 (𝜌 )𝛿2 ) 𝐴2/3
This talk: Stellar matter versus nuclear matter phase diagram
The sub-saturation regime : Coulomb effects and dishomogeneous phases
The super-saturation regime: Hyperonic matter & strangeness phase transition
T
rBpasta
QGP???
Hyperons in dense stellar matter Hypernuclei: L
potential attractive at low density
Hyperon d.o.f tend to soften the EoS
Still compatible with 2Mo NS if the hyperon-hyperon coupling is strongly repulsive at high density
M.Oertel et al, http://arxiv.org/abs/1202.2679
I.Vidana et al, Europhys.Lett.94:11002,2011
Strangeness phase transition Attractive NL and LL
interaction at low rB
, repulsive at high rB e(r) has a minimum =>dilute/dense PT ? erL has a minimum
=> non-strange/strange PT ? Illustration with a simple
model: n-L equilibrium in the HF approximation; energy functional from Balberg & Gal
S.Balberg A.Gal NPA 625(1997)435
YL=
rn=0.45 fm-3
rn=0.3 fm-3
rn=0.15 fm-3
rr rS(fm-3)
n-L phase diagram different first and second
order phase transitions I: L’s in neutron matter II: n-L liquid-gas III: neutrons in L matter
F.G.,A.Raduta and M.Oertel, in preparation
n-L phase diagram different first and second
order phase transitions I: L’s in neutron matter II: n-L liquid-gas III: neutrons in L matter
F.G.,A.Raduta and M.Oertel, in preparation
S =0
n-L phase diagram different first and second
order phase transitions I: L’s in neutron matter II: n-L liquid-gas III: neutrons in L matter
=> Coexisting hyperon-rich & hyperon-poor regions along the physical trajectory S=0
F.G.,A.Raduta and M.Oertel, in preparation
S =0
S
=0
n-L phase diagram different first and second
order phase transitions I: L’s in neutron matter II: n-L liquid-gas III: neutrons in L matter
=> Coexisting hyperon-rich & hyperon-poor regions along the physical trajectory S=0=> Explores a critical point at T>0: n opacity?
F.G.,A.Raduta and M.Oertel, in preparation
S =0
criti
cal p
oint
J.Margueron et al, PRC70 (2004) 028801
S
=0
Conclusion: Stellar matter phase diagram
The sub-saturation regime : Coulomb effects and phase transition quenching A specific thermodynamics Wide distribution of clusters Important for e-capture and n -interaction
The super-saturation regime: A possible strangeness phase transition Consequences on EoS, NS mass, n - transport ? Constraints on Y-N and Y-Y interaction needed
28/27
Frustration and dishomogeneous phases Frustration is a generic
phenomenon in physics It occurs whenever matter
is subject to opposite interactions (here: nuclear & coulomb) on comparable length scales
Global variations of the order parameter (here: density) are replaced by local variations
=>Phase coexistence is quenched
=>dishomogeneous phases arise
=>Ensemble equivalence is violated q
T
Tcr
dishomogeneousphase
P.Viot G.Tarjus PRE2001
Example: frustrated Ising ferromagnets
P.Viot G.Tarjus PRE2001
Fe,
2 2
avec 0
N
N
s sq'H s sr
M s
=
= =
i ji j
i j i j ij
ii
• Frustration in soft-matter: diblock copolymer melts, cross linked
copolymer mixtures, interpenetrating networks, oil-water surfactant mixtures• Frustration in magnetism: ultrathin magnetic films• Frustration in glasses: doped Mott insulator, supercooled liquids
q
T
Tcr
dishomogeneousphase