TIME-DEPENDENT MULTI-GROUP MULTI-DIMENSIONAL RELATIVISTIC RADIATIVE TRANSFER CODE BASED ON SPHERICAL HARMONIC DISCRETE ORDINATE METHOD

Journal Article · Sat Aug 15 00:00:00 EDT 2015 · Astrophysical Journal, Supplement Series

DOI:https://doi.org/10.1088/0067-0049/219/2/38· OSTI ID:22520150

Tominaga, Nozomu; Shibata, Sanshiro ^[1]

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1. Department of Physics, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Kobe, Hyogo 658-8501 (Japan)

We develop a time-dependent, multi-group, multi-dimensional relativistic radiative transfer code, which is required to numerically investigate radiation from relativistic fluids that are involved in, e.g., gamma-ray bursts and active galactic nuclei. The code is based on the spherical harmonic discrete ordinate method (SHDOM) which evaluates a source function including anisotropic scattering in spherical harmonics and implicitly solves the static radiative transfer equation with ray tracing in discrete ordinates. We implement treatments of time dependence, multi-frequency bins, Lorentz transformation, and elastic Thomson and inelastic Compton scattering to the publicly available SHDOM code. Our code adopts a mixed-frame approach; the source function is evaluated in the comoving frame, whereas the radiative transfer equation is solved in the laboratory frame. This implementation is validated using various test problems and comparisons with the results from a relativistic Monte Carlo code. These validations confirm that the code correctly calculates the intensity and its evolution in the computational domain. The code enables us to obtain an Eddington tensor that relates the first and third moments of intensity (energy density and radiation pressure) and is frequently used as a closure relation in radiation hydrodynamics calculations.

• OSTI ID: 22520150
• Journal Information: Astrophysical Journal, Supplement Series, Vol. 219, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0067-0049
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COMPARATIVE EVALUATIONS
COMPTON EFFECT
COSMIC GAMMA BURSTS
DISCRETE ORDINATE METHOD
ENERGY DENSITY
GALAXY NUCLEI
HYDRODYNAMICS
LORENTZ TRANSFORMATIONS
MONTE CARLO METHOD
RADIANT HEAT TRANSFER
RADIATION PRESSURE
RELATIVISTIC RANGE
S CODES
SHOCK WAVES
SPHERICAL CONFIGURATION
SPHERICAL HARMONICS
TENSORS
TIME DEPENDENCE