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Related papers: A 3D radiative transfer framework: VI. PHOENIX/3D …

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We describe a highly flexible framework to solve 3D radiation transfer problems in scattering dominated environments based on a long characteristics piece-wise parabolic formal solution and an operator splitting method. We find that the…

Astrophysics · Physics 2009-11-11 Peter H. Hauschildt , E. Baron

We discuss three issues in the context of three-dimensional (3D) hydrodynamical model atmospheres for late-type stars, related to spectral line shifts, radiative transfer in metal-poor 3D models, and the solar oxygen abundance. We include a…

Astrophysics · Physics 2009-11-13 Hans-G. Ludwig , Matthias Steffen

We present a general method to solve radiative transfer problems including scattering in the continuum as well as in lines in 3D configurations with periodic boundary conditions. he scattering problem for line transfer is solved via means…

Astrophysics · Physics 2009-11-13 Peter H. Hauschildt , E. Baron

We present a new numerical model called "Pakal" intended to solve the radiative transfer equation in a three-dimensional (3D) geometry, using the approximation for a locally plane-parallel atmosphere. Pakal uses pre-calculated radial…

Solar and Stellar Astrophysics · Physics 2011-06-14 Victor De la Luz , Alejandro Lara , J. E. Mendoza-Torres , Caius L. Selhorst

We introduce two new methods that are designed to improve the realism and utility of large, active region-scale 3D MHD models of the solar atmosphere. We apply these methods to RADMHD, a code capable of modeling the Sun's upper convection…

Solar and Stellar Astrophysics · Physics 2010-05-06 William P. Abbett , George H. Fisher

The study of planetary atmospheres is crucial for understanding the origin, evolution, and processes that shape celestial bodies like planets, moons and comets. The interpretation of planetary spectra requires a detailed understanding of…

Earth and Planetary Astrophysics · Physics 2023-10-31 Miriam Rengel , Jakob Adamczewski

Context: State of the art quantitative spectroscopy of OB-stars compares synthetic spectra (calculated by means of 1D, spherically symmetric computer codes) with observations. Certain stellar atmospheres, however, show strong deviations…

Solar and Stellar Astrophysics · Physics 2018-09-12 L. Hennicker , J. Puls , N. D. Kee , J. O. Sundqvist

Transmission spectroscopy is one of the premier methods used to probe the temperature, composition, and cloud properties of exoplanet atmospheres. Recent studies have demonstrated that the multidimensional nature of exoplanet atmospheres --…

Earth and Planetary Astrophysics · Physics 2022-04-20 Ryan J. MacDonald , Nikole K. Lewis

Radiative-transfer (RT) is a key component for investigating atmospheres of planetary bodies. With the 3D nature of exoplanet atmospheres being important in giving rise to their observable properties, accurate and fast 3D methods are…

We present an extensively updated version of the purely ray-tracing 3D dust radiation transfer code DART-Ray. The new version includes five major upgrades : 1) a series of optimizations for the ray-angular density and the scattered…

The atmospheres of planets (including Earth) and the outer layers of stars have often been treated in radiative transfer as plane-parallel media, instead of spherical shells, which can lead to inaccuracy, e.g. limb darkening. We give an…

Statistical Mechanics · Physics 2009-11-11 Michael J. Caola

Accurate angular quadratures are crucial for the numerical solution of three-dimensional (3D) radiative transfer problems, especially when the spectral line polarisation produced by the scattering of anisotropic radiation is included. There…

Solar and Stellar Astrophysics · Physics 2021-01-27 Jaume Jaume Bestard , Jiří Štěpán , Javier Trujillo Bueno

Non-LTE radiative transfer is a key tool for modern astrophysics: it is the means by which many key synthetic observables are produced, thus connecting simulations and observations. Radiative transfer models also inform our understanding of…

Solar and Stellar Astrophysics · Physics 2025-11-12 Christopher M. J. Osborne , Alexander Sannikov

We simulate convection near the solar surface, where the continuum optical depth is of order unity. Hence, to determine the radiative heating and cooling in the energy conservation equation, we must solve the radiative transfer equation…

Astrophysics · Physics 2007-05-23 Robert Stein , Aake Nordlund

A parallel dispersive finite-difference time-domain (FDTD) method for the modeling of three-dimensional (3-D) electromagnetic cloaking structures is presented in this paper. The permittivity and permeability of the cloak are mapped to the…

Computational Physics · Physics 2015-05-13 Yan Zhao , Yang Hao

Context. Magnetic fields are important to the dynamics of many astrophysical processes and can typically be studied through polarization observations. Polarimetric interferometry capabilities of modern (sub)millimeter telescope facilities…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 Boy Lankhaar , Wouter Vlemmings

A novel 3-D higher-order finite-difference time-domain framework with complex frequency-shifted perfectly matched layer for the modeling of wave propagation in cold plasma is presented. Second- and fourth-order spatial approximations are…

Plasma Physics · Physics 2013-10-25 Konstantinos P. Prokopidis

3D non-LTE radiative transfer problems are computationally demanding, and this sets limits on the size of the problems that can be solved. So far Multilevel Accelerated Lambda Iteration (MALI) has been to the method of choice to perform…

Solar and Stellar Astrophysics · Physics 2017-03-15 Johan P. Bjørgen , Jorrit Leenaarts

Radiation transfer is an important topic in several physical disciplines, probably most prominently in astrophysics. Computer scientists use radiation transfer, among other things, for the visualisation of complex data sets with direct…

Instrumentation and Methods for Astrophysics · Physics 2014-10-24 Thomas Peters

Context. The magnetic field in the solar atmosphere continually reconnects and accelerates charged particles to high energies. Simulations of the atmosphere in three dimensions that include the effects of accelerated particles can aid our…

Solar and Stellar Astrophysics · Physics 2022-10-05 L. Frogner , B. V. Gudiksen