Phase Transitions

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workshop ESNT "Mean Field and Beyond for Nuclear
Reactions"
Phase Transitions frustration in nuclear
physics and astrophysics
Karim Hasnaoui(1)
Ph. Chomaz(1), C. Ducoin(1,2), F. Gulminelli(2),
P. Napolitani(1) (1) GANIL (DSM-CEA/IN2P3-CNRS),B
lvd. H. Becquerel, F-14076 Caen cédex, France (2)
LPC Caen (IN2P3-CNRS/Ensicaen et Université),
F-14050 Caen cédex, France
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Nuclear matter and neutron stars

• Matter of neutrons, protons, and electrons.
• Crust of star Þ r/ r0 Î 0.1,1.

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Motivation of the project

• Exotic phases. (J.C. Pethick D.G. Ravenhall).
• To understand the phenomenology of phase
  transitions of nuclear matter.
• To study the opalescence of star matter for
  neutrino propagation. (C. Horowitz al)

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Ising analogue to compact star matter
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Ising analogue to compact star matter
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Matrice Cij
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Result 1 Equation of state
system uncharged
system charged

• Liquid-gas coexistence expands with respect to
  uncharged nuclear matter gt Ttransition gt Tc

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Result 2 Criticality

• The phase transition is not of the second order.
• The lengths of correlations do not diverge at
  the point of transition.

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Effective interactions

• The phase-transition phenomenology depends on
  the intrinsic interaction gt Necessary to use an
  effective interaction.
• to take into account
• Fermionic character of the nuclear system.
• Isospin degree of freedom.

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Fermionic Molecular Dynamics (FMD) (H.Feldmeier
al)
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Fermionic Molecular Dynamics (FMD) (H.Feldmeier
al)
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Conclusion and perspectives

• ISING gt Coulomb modifies the phase-transitions
  phenomenology gt suppression of criticality
• FMD gt to take effective interactions and
  dynamics into account.
• Other exotic phases of the crust.
• Neutrino propagation.