English
Related papers

Related papers: An implementation of radiative transfer in the cos…

200 papers

We present a new hybrid Smoothed Particle Hydrodynamics (SPH)/N-body method for modelling the collisional stellar dynamics of young clusters in a live gas background. By deriving the equations of motion from Lagrangian mechanics we obtain a…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 D. A. Hubber , R. J. Allison , R. Smith , S. P. Goodwin

We present Variable Eddington Tensor-closed Transport on Adaptive Meshes (\texttt{VETTAM}), a new algorithm to solve the equations of radiation hydrodynamics (RHD) with support for adaptive mesh refinement (AMR) in a frequency-integrated,…

Instrumentation and Methods for Astrophysics · Physics 2022-03-02 Shyam H. Menon , Christoph Federrath , Mark R. Krumholz , Rolf Kuiper , Benjamin D. Wibking , Manuel Jung

We present a method for general relativistic smoothed particle hydrodynamics (GRSPH), based on an entropy-conservative form of the general relativistic hydrodynamic equations for a perfect fluid. We aim to replace approximate treatments of…

Instrumentation and Methods for Astrophysics · Physics 2019-01-25 David Liptai , Daniel J. Price

Cosmological simulations of reionization often treat radiative transfer by solving for the monopole and dipoles of the intensity field and by making ansatz for the quadrupole moments to close the system of equations. We investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-03 Xiaohan Wu , Matthew McQuinn , Daniel Eisenstein

We present an implementation of Smoothed Particle Hydrodynamics (SPH) in an adaptive-mesh PPPM algorithm. The code evolves a mixture of purely gravitational particles and gas particles. The code retains the desirable properties of previous…

Astrophysics · Physics 2009-10-22 H. M. P. Couchman , P. A. Thomas , F. R. Pearce

For simulations that deal only with dark matter or stellar systems, the conventional N-body technique is fast, memory efficient, and relatively simple to implement. However when including the effects of gas physics, mesh codes are at a…

Instrumentation and Methods for Astrophysics · Physics 2012-11-21 Nigel L. Mitchell , Eduard I. Vorobyov , Gerhard Hensler

In this work, we prove rigorous error estimates for a hybrid method introduced in [15] for solving the time-dependent radiation transport equation (RTE). The method relies on a splitting of the kinetic distribution function for the…

Numerical Analysis · Mathematics 2023-06-09 Andrés Galindo-Olarte , Victor P. DeCaria , Cory D. Hauck

We describe a new algorithm for including the dynamical effects of ionizing radiation in SPH simulations, and we present several examples of how the algorithm can be applied to problems in star formation. We use the HEALPix software to…

Solar and Stellar Astrophysics · Physics 2009-11-13 T. G. Bisbas , R. Wunsch , A. P. Whitworth , D. A. Hubber

We adapt a modern scheme of smoothed particle hydrodynamics (SPH) to our tree N-body/SPH galactic chemodynamics code GCD+. The applied scheme includes imple- mentations of the artificial viscosity switch and artificial thermal conductivity…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Daisuke Kawata , Takashi Okamoto , Brad K. Gibson , David J. Barnes , Renyue Cen

We propose a novel Skew Gradient Embedding (SGE) framework for systematically reformulating thermodynamically consistent partial differential equation (PDE) models-capturing both reversible and irreversible processes-as generalized gradient…

Numerical Analysis · Mathematics 2025-09-24 Xuelong Gu , Qi Wang

We consider the numerical approximation of boundary conditions in radiative transfer problems by a perfectly matched layer approach. The main idea is to extend the computational domain by an absorbing layer and to use an appropriate…

Numerical Analysis · Mathematics 2018-02-26 Herbert Egger , Matthias Schlottbom

Solving the continuum radiative transfer equation in high opacity media requires sophisticated numerical tools. In order to test the reliability of such tools, we present a benchmark of radiative transfer codes in a 2D disc configuration.…

Solar and Stellar Astrophysics · Physics 2015-05-13 C. Pinte , T. J. Harries , M. Min , A. M. Watson , C. P. Dullemond , P. Woitke , F. Menard , M. C. Duran-Rojas

This paper presents a comprehensive numerical framework for simulating radiation-plasma systems. The radiative transfer process spans multiple flow regimes due to varying fluid opacity across different regions, necessitating a robust…

Astrophysics of Galaxies · Physics 2025-12-24 Mingyu Quan , Kun Xu

Numerical methods for radiative transfer play a key role in modern-day astrophysics and cosmology, including study of the inhomogeneous reionization process. In this context, ray tracing methods are well-regarded for accuracy but notorious…

Instrumentation and Methods for Astrophysics · Physics 2025-12-16 Nathan X. Marshak , Kathlynn Simotas , Zarija Lukić , Hyunbae Park , James Ahrens , Chris R. Johnson

This paper describes a new fast and implicitly parallel approach to neighbour-finding in multi-resolution Smoothed Particle Hydrodynamics (SPH) simulations. This new approach is based on hierarchical cell decompositions and sorted…

Distributed, Parallel, and Cluster Computing · Computer Science 2014-04-10 Pedro Gonnet

Cosmological simulations of structure formation follow the collisionless evolution of dark matter starting from a nearly homogeneous field at early times down to the highly clustered configuration at redshift zero. The density field is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Francesca Iannuzzi , Klaus Dolag

Context: Radiative transfer modelling of expanding stellar envelopes is an important task in their analysis. To account for inhomogeneities and deviations from spherical symmetry, it is necessary to develop a 3D approach to radiative…

Solar and Stellar Astrophysics · Physics 2023-02-08 Jakub Fišák , Jiří Kubát , Brankica Kubátová , Markus Kromer , Jiří Krtička

This article presents an on-line tool (rttools.irap.omp.eu) and its accompanying software ressources for the numerical solution of basic radiation transfer out of local thermodynamic equilibrium (LTE). State-of-the-art stationary iterative…

Instrumentation and Methods for Astrophysics · Physics 2015-12-09 J. Lambert , F. Paletou , E. Josselin , J. -M. Glorian

We introduce SPHRAY, a Smoothed Particle Hydrodynamics (SPH) ray tracer designed to solve the 3D, time dependent, radiative transfer (RT) equations for arbitrary density fields. The SPH nature of SPHRAY makes the incorporation of separate…

Astrophysics · Physics 2009-11-13 Gabriel Altay , Rupert A. C. Croft , Inti Pelupessy

We introduce a novel algorithm, $\textit{COD}$ -- Compact Opacity Distribution, for shape reconstruction of a celestial body that has been observed to occult a star, using the photometric time-series observations of the occultation.…

Instrumentation and Methods for Astrophysics · Physics 2022-02-08 Gil Nachmani , Tsevi Mazeh , Nir Sochen
‹ Prev 1 8 9 10 Next ›