A Finite Difference Representation of Neutrino Radiation Hydrodynamics in Spherically Symmetric General Relativistic Spacetime

By M. Liebendoerfer, O. E. Bronson Messer, A. Mezzacappa, S. Bruenn, C. Cardall, F. Thielemann. 2002

199 citations recorded by the source corpus.

We present an implicit finite difference representation for general relativistic radiation hydrodynamics in spherical symmetry. Our code, AGILE-BOLTZTRAN, solves the Boltzmann transport equation for the angular and spectral neutrino distribution functions in self-consistent simulations of stellar core collapse and postbounce evolution. It implements a dynamically adaptive grid in comoving coordinates. A comoving frame in the momentum phase space facilitates the evaluation and tabulation of neutrino-matter interaction cross sections but produces a multitude of observer corrections in the transport equation. Most macroscopically interesting physical quantities are defined by expectation values of the distribution function. We optimize the finite differencing of the microscopic transport equation for a consistent evolution of important expectation values. We test our code in simulations launched from progenitor stars with 13 solar masses and 40 solar masses. Half a second after core collapse and bounce, the protoneutron star in the latter case reaches its maximum mass and collapses further to form a black hole. When the hydrostatic gravitational contraction sets in, we find a transient increase in electron flavor neutrino luminosities due to a change in the accretion rate. The μ- and τ-neutrino luminosities and rms energies, however, continue to rise because previously shock-heated material with a nondegenerate electron gas starts to replace the cool degenerate material at their production site. We demonstrate this by supplementing the concept of neutrinospheres with a more detailed statistical description of the origin of escaping neutrinos. Adhering to our tradition, we compare the evolution of the 13 M⊙ progenitor star to corresponding simulations with the multigroup flux-limited diffusion approximation, based on a recently developed flux limiter. We find similar results in the postbounce phase and validate this MGFLD approach for the spherically symmetric case with standard input physics.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/39138c87da9bd069c8a29e7b0f67c457f7c43173

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Citations in the corpus

Supernova Simulations with Boltzmann Neutrino Transport: A Comparison of Methods (2003, methodology): “The finite-differencing has been revised for energy conservation and extended to solve the general relativistic equations (2)–(8) (Liebendörfer 2000; Liebendörfer et al. 2002, 2004).”
Protoneutron star evolution and the neutrino-driven wind in general relativistic neutrino radiation hydrodynamics simulations (2009, methodology): “For details see Mezzacappa and Bruenn (1993 a-c), Mezzacappa and Messer (1999), Liebendörfer et al. (2001a,b) and Liebendörfer et al. (2004).”
What can be learned from a future supernova neutrino detection (2017, background): “binding energy and with the increasing density, for a brief period, the luminosity and the mean energies of the μ and τ flavour neutrinos actually increase [198].”
Composition of the Innermost Core-Collapse Supernova Ejecta (2004, methodology): “The framework for this investigation are spherically symmetric simulations with implicit general relativistic Boltzmann neutrino transport, see Mezzcappa & Messer (1999) and Liebendörfer et al. (2004) for a detailed description of the code agile-boltztran.”
THE ISOTROPIC DIFFUSION SOURCE APPROXIMATION FOR SUPERNOVA NEUTRINO TRANSPORT (2007, methodology): “This is achieved by a geometric estimate of the flux factor as suggested and evaluated by Bruenn in (Liebendörfer et al. 2004).”
THE DEVELOPMENT OF EXPLOSIONS IN AXISYMMETRIC AB INITIO CORE-COLLAPSE SUPERNOVA SIMULATIONS OF 12–25 M ⊙ ?> STARS (2012, methodology): “…forty years after Colgate and White’s original proposal, with simulations that implemented general relativistic Boltzmann neutrino transport and hydrodynamics coupled to general relativistic gravity, using state of the art weakinteractions and equations of state (Liebendörfer et al. 2001, 2004).”
Explosion mechanism, neutrino burst and gravitational wave in core-collapse supernovae (2005, methodology): “The thin and thick lines are based on the simulations of a 15M progenitor star, performed by vertex code of the Garching group [295] and agile-boltztran code of Oak Ridge-Basel group [221], respectively.”
Two-dimensional hydrodynamic core-collapse supernova simulations with spectral neutrino transport II. Models for different progenitor stars (2005, unknown): “…requests to: H.-Th. Janka, e-mail: thj@mpa-garching.mpg.de ⋆ Present address: Rechenzentrum der Max-Planck-Gesellschaft am Max-Planck-Institut für Plasmaphysik, Boltzmannstr.2, D-85748 Garching, Germany Janka 2002; Liebendörfer et al. 2001, 2004; Thompson et al. 2003; Sumiyoshi et al. 2005).”