Stellar core collapse: II. Inner core bounce and shock propagation

Journal Article · Tue Jun 15 00:00:00 EDT 1982 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/160032· OSTI ID:7064043

Van Riper, K A

The evolution of a collapsing core of 15 M/sub sun/ star is followed, by numerical simulation, from a central density of 10/sup 14/ g cm/sup -3/, through homologous core bounce, until the outward motion of the shock front ceases a few milliseconds after bounce. The infall of these models was described in Van Riper and Lattimer. The models use the equation of state of Lamb, Lattimer, Pethick, and Ravenhall below nuclear density and general relativistic hydrodynamics. The transport of neutrinos, both from electron caputres and from thermal production of ..nu../sub ..mu../-nu-tilde/sub ..mu../ and ..nu../sub tau/-nu-tilde/sub tau/ pairs, is treated by a leakage scheme. Homologous cores bounce at twice nuclear density, and do not oscillate after bounce if the properties of matter above nuclear density are described by the Friedman and Pandharipande equation of state. A shock wave forms at the surface of the bouncing core, and propagates outward in space until the postshock density is too low to trap the electron neutrinos, which are copiously produced by captures on the free protons in the dissociated matter behind the shock. These neutrinos carry away a large fraction of the internal energy gained by matter passing through the shock, leading to sever weaking of the shock. A deep lepton inversion develops behind the shock. Postshock entropies reach a maximum between 7 and 10 k/sub B/ baryon/sup -/2exclamation, with the higher values resulting from more massive homologous cores. Several models are considered, showing that the final shock weakening occurs regardless of the neutrino trapping density and the equation of state above nuclear density.

• Research Organization: Department of Physics, Univeristy of Illinois at Urbana-Champaign; and University of California, Los Alamos National Labortory, Applied Theoretical Physics Division, Computational Physics Group
• OSTI ID: 7064043
• Journal Information: Astrophys. J.; (United States), Vol. 257:2
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
STARS
EQUATIONS OF STATE
GRAVITATIONAL COLLAPSE
NEUTRINOS
SHOCK WAVES
ELECTRON CAPTURE
ENTROPY
HYDRODYNAMICS
LEPTONS
NUMERICAL SOLUTION
PLASMA
STAR EVOLUTION
STAR MODELS
WAVE PROPAGATION
CAPTURE
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FLUID MECHANICS
MASSLESS PARTICLES
MATHEMATICAL MODELS
MECHANICS
PHYSICAL PROPERTIES
THERMODYNAMIC PROPERTIES
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
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