English
Related papers

Related papers: Solution of the radiative transfer equation in the…

200 papers

A finite element approach for approximating the solution of a mathematical model for the response of a penetrable, bounded object (obstacle) to the excitation by an external electromagnetic field is presented and investigated. The model…

Numerical Analysis · Mathematics 2026-04-16 Lutz Angermann

The radiation transport problem in the plane-parallel medium with the large velocity gradient is considered. The Sobolev approximation is used. The effects of continuum absorption and line overlap are taken into account. The photon loss…

Astrophysics of Galaxies · Physics 2021-02-03 Aleksandr Nesterenok

We present a new method for the numerical solution of the radiative-transfer equation (RTE) in multidimensional scenarios commonly encountered in computational astrophysics. The method is based on the direct solution of the Boltzmann…

Computational Physics · Physics 2020-10-06 L. R. Weih , A. Gabbana , D. Simeoni , L. Rezzolla , S. Succi , R. Tripiccione

We present {\tt radpol} - a numerical scheme for integrating multifrequency polarized radiative transfer equations along rays propagating in a curved spacetime. The scheme includes radiative processes such as synchrotron emission,…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Monika Moscibrodzka

We study the systematic numerical approximation of Maxwell's equations in dispersive media. Two discretization strategies are considered, one based on a traditional leapfrog time integration method and the other based on convolution…

Numerical Analysis · Mathematics 2020-04-02 Jürgen Dölz , Herbert Egger , Vsevolod Shashkov

We describe a code designed for hot media {(T $\ge$} a few 10$^4$ K), optically thick to Compton scattering. It computes the structure of a plane-parallel slab of gas in thermal and ionization equilibrium, illuminated on one side or on both…

Astrophysics · Physics 2009-09-25 Anne-Marie Dumont , Suzy Collin

Context: The solution of the nonlocal thermodynamical equilibrium (non-LTE) radiative transfer equation usually relies on stationary iterative methods, which may falsely converge in some cases. Furthermore, these methods are often unable to…

Solar and Stellar Astrophysics · Physics 2015-07-29 Julien Lambert , Eric Josselin , Nils Ryde , Alexandre Faure

Simple finite differencing of the anisotropic diffusion equation, where diffusion is only along a given direction, does not ensure that the numerically calculated heat fluxes are in the correct direction. This can lead to negative…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Prateek Sharma , Gregory W. Hammett

The development of an analytically iterative method for solving steady-state as well as unsteady-state problems of cosmic-ray (CR) modulation is proposed. Iterations for obtaining the solutions are constructed for the spherically symmetric…

Instrumentation and Methods for Astrophysics · Physics 2017-07-04 Yuriy L. Kolesnyk , Pavol Bobik , Boris A. Shakhov , Marian Putis

The transition-matrix ($T$-matrix) approach provides a general formalism to study scattering problems in various areas of physics, including acoustics (scalar fields) and electromagnetics (vector fields), and is related to the theory of the…

Optics · Physics 2016-02-08 Eric C. Le Ru , Walter R. C. Somerville , Baptiste Auguié

We present exact analytical bright and dark (black and grey) solitary wave solutions of a nonlinear Schrodinger-type equation describing the propagation of spatial beams in media exhibiting a saturable nonlinearity (such as centrosymmetric…

Exactly Solvable and Integrable Systems · Physics 2015-05-13 Gabriel F. Calvo , Juan Belmonte-Beitia , Victor M. Perez-Garcia

The aim of this work is to formulate two new solutions by decoupling the field equations via a minimal geometric deformation in the context of self-interacting Brans-Dicke gravity. We introduce an extra source in the anisotropic fluid…

General Relativity and Quantum Cosmology · Physics 2022-01-14 M. Sharif , Amal Majid

This work introduces original explicit solutions for the elastic fields radiated by non-uniformly moving, straight, screw or edge dislocations in an isotropic medium, in the form of time-integral representations in which…

Classical Physics · Physics 2016-09-26 Markus Lazar , Yves-Patrick Pellegrini

This paper is concerned with the electromagnetic inverse scattering problem that aims to determine the location and shape of anisotropic scatterers from far field data (at a fixed frequency). We study the orthogonality sampling method which…

Analysis of PDEs · Mathematics 2019-11-05 Isaac Harris , Dinh-Liem Nguyen

Numerical discretization of the large-scale Maxwell's equations leads to an ill-conditioned linear system that is challenging to solve. The key requirement for successive solutions of this linear system is to choose an efficient solver. In…

Numerical Analysis · Mathematics 2023-01-31 Sahar Borzooei , Victorita Dolean , Pierre-Henri Tournier , Claire Migliaccio

We derive a nonlinear moment model for radiative transfer equation in 3D space, using the method to derive the nonlinear moment model for the radiative transfer equation in slab geometry. The resulted 3D HMPN model enjoys a list of…

Computational Physics · Physics 2020-05-28 Ruo Li , Peng Song , Lingchao Zheng

(Abridged) We describe a new algorithm for solving the coupled frequency-integrated transfer equation and the equations of magnetohydrodynamics when the light-crossing time is only marginally shorter than dynamical timescales. The transfer…

Instrumentation and Methods for Astrophysics · Physics 2014-06-24 Yan-Fei Jiang , James M. Stone , Shane W. Davis

We present the geometry and symmetries of radiative transfer theory. Our geometrization exploits recent work in the literature that enables to obtain the Hamiltonian formulation of radiative transfer as the semiclassical limit of a phase…

Mathematical Physics · Physics 2013-07-30 Christian Lessig , Alex L. Castro

In this paper we introduce a new fix point iteration scheme for solving nonlinear electromagnetic scattering problems. The method is based on a spectral formulation of Maxwell's equations called the Bidirectional Pulse Propagation…

Classical Physics · Physics 2026-03-27 Per Kristen Jakobsen

The transfer equation in spherical geometry with central symmetry, which is a partial differential equation in two variables r and m, is reduced to a one-dimensional transfer equation in r parametric in m. This is done by dropping the…

Astrophysics · Physics 2007-05-23 Charles H Aboughantous
‹ Prev 1 8 9 10 Next ›