Role of isospin physics in supernova matter and neutron stars

Journal Article · Mon Nov 15 00:00:00 EST 2010 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.82.055802· OSTI ID:21499218

Sharma, Bharat K; Pal, Subrata ^[1]

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1. Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India)

We investigate the liquid-gas phase transition of hot protoneutron stars shortly after their birth following supernova explosion and the composition and structure of hyperon-rich (proto)neutron stars within a relativistic mean-field model where the nuclear symmetry energy was constrained from the measured neutron skin thickness of finite nuclei. Light clusters are abundantly formed with increasing temperature well inside the neutrino-sphere for a uniform supernova matter. Liquid-gas phase transition is found to suppress the cluster yield within the coexistence phase as well as decrease considerably the neutron-proton asymmetry over a wide density range. We find symmetry energy has a modest effect on the boundaries and the critical temperature for the liquid-gas phase transition, and the composition depends more sensitively on the number of trapped neutrinos and temperature of the protoneutron star. The influence of hyperons in the dense interior of stars makes the overall equation of state soft. However, neutrino trapping distinctly delays the appearance of hyperons because of an abundance of electrons. We also find that a softer symmetry energy further makes the onset of hyperon less favorable. The resulting structures of the (proto)neutron stars with hyperons and with liquid-gas phase transition are discussed.

• OSTI ID: 21499218
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 82, Issue 5; Other Information: DOI: 10.1103/PhysRevC.82.055802; (c) 2010 The American Physical Society; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASYMMETRY
CRITICAL TEMPERATURE
ELECTRONS
EQUATIONS OF STATE
EXPLOSIONS
HYPERONS
ISOSPIN
MEAN-FIELD THEORY
NEUTRINOS
NEUTRON STARS
NEUTRONS
NUCLEI
PHASE TRANSFORMATIONS
PROTONS
RELATIVISTIC RANGE
SUPERNOVAE
SYMMETRY
BARYONS
BINARY STARS
ELEMENTARY PARTICLES
ENERGY RANGE
EQUATIONS
ERUPTIVE VARIABLE STARS
FERMIONS
HADRONS
LEPTONS
MASSLESS PARTICLES
NUCLEONS
PARTICLE PROPERTIES
PHYSICAL PROPERTIES
STARS
STRANGE PARTICLES
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
VARIABLE STARS