Maximum entropy distribution and closure for Bose-Einstein and Fermi-Dirac radiation transport

Abstract

view Abstract Citations (46) References (11) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Maximum Entropy Distribution and Closure for Bose-Einstein and Fermi-Dirac Radiation Transport Cernohorsky, J. ; Bludman, S. A. Abstract We derive and study the variable Eddington factors following without approximation from the maximum entropy distribution. A unified formalism is developed for classical Maxwell-Boltzmann, Bose-Einstein, and Fermi-Dirac radiation. In the classical and high occupancy limits the maximum entropy closure is bounded by previously known variable Eddington factors that depend only on the flux: the Levermore-Pomraning closure for Bose radiation at high occupation density and Minerbo's flux-limiter for the Boltzmann limit of either quantum statistics. For immediate occupancy, the maximum entropy closure depends on both the occupation density and the flux. The Fermi-Dirac maximum entropy variable Eddington factor exhibits scale invariance, which leads to a simple analytic closure for fermion radiation. This Fermi-Dirac variable Eddington factor agrees well with Monte Carlo neutrino transport closures during early stages of neutron star formation. Publication: The Astrophysical Journal Pub Date: September 1994 DOI: 10.1086/174640 Bibcode: 1994ApJ...433..250C Keywords: Eddington Approximation; Fermi-Dirac Statistics; Maximum Entropy Method; Neutron Stars; Quantum Statistics; Radiation Transport; Star Formation; Stellar Radiation; Closure Law; Formalism; Maxwell-Boltzmann Density Function; Neutrinos; Transport Properties; Astrophysics; RADIATION MECHANISMS: NONTHERMAL; STARS: NEUTRON full text sources ADS |