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Related papers: Non-LTE radiation hydrodynamics in PLUTO

200 papers

This review paper outlines background information and covers recent advances made via the analysis of spectra and images of prominence plasma and the increased sophistication of non-LTE (ie when there is a departure from Local Thermodynamic…

Solar and Stellar Astrophysics · Physics 2011-05-10 N. Labrosse , P. Heinzel , J. -C. Vial , T. Kucera , S. Parenti , S. Gunar , B. Schmieder , G. Kilper

The dynamics of molecular clouds is characterized by supersonic random motions in the presence of a magnetic field. We study this situation using numerical solutions of the three-dimensional compressible magneto-hydrodynamic (MHD) equations…

Astrophysics · Physics 2009-10-30 Paolo Padoan , Mika Juvela , John Bally , AAke Nordlund

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

Shocks are often invoked as heating mechanisms in astrophysical systems, with both adiabatic compression and dissipative heating that leading to temperature increases. Whilst shocks are reasonably well understood for ideal…

Solar and Stellar Astrophysics · Physics 2024-01-03 Ben Snow

Non-equilibrium radiation is addressed theoretically by means of a stochastic lattice-gas model. We consider a resonating transmission line composed of a chain of radiation resonators, each at a local equilibrium, whose boundaries are in…

Statistical Mechanics · Physics 2022-07-05 Boris Rotstein , Eric Akkermans

We describe a new algorithm to solve the time dependent, frequency integrated radiation transport (RT) equation implicitly, which is coupled to an explicit solver for equations of magnetohydrodynamics (MHD) using {\sf Athena++}. The…

Instrumentation and Methods for Astrophysics · Physics 2021-04-07 Yan-Fei Jiang

Radiative cooling plays a crucial role in the dynamics of many astrophysical flows, and is particularly important in the dense shocked gas within Herbig-Haro (HH) objects and stellar jets. Simulating cooling processes accurately is…

High Energy Astrophysical Phenomena · Physics 2018-11-19 E. C. Hansen , P. Hartigan , A. Frank. A. Wright , J. C. Raymond

We discuss the current implementation of the ALI method into our HYDrodynamical RAdiation(HYDRA) code for rapidly expanding, low density envelopes commonly found in core collapse and thermonuclear supernovae, novae and WR stars. Due to the…

Astrophysics · Physics 2007-05-23 P. Hoeflich

We have developed a new massively-parallel radiation-hydrodynamics code (Cosmos) for Newtonian and relativistic astrophysical problems that also includes radiative cooling, self-gravity, and non-equilibrium, multi-species chemistry. Several…

Astrophysics · Physics 2009-11-07 Peter Anninos , P. Chris Fragile , Stephen D. Murray

We demonstrate the potential for research and outreach of mixed polygon and hydrodynamic modeling and multi-waveband rendering in the interactive 3-D astrophysical virtual laboratory Shape. In 3-D special effects and animation software for…

Instrumentation and Methods for Astrophysics · Physics 2017-06-19 Wolfgang Steffen , Nico Koning

Radiative opacity is an important quantity in the modeling of stellar structure and evolution. In the present work we recall the role of opacity in the interpretation of pulsations of different kinds of stars. The detailed opacity code…

Solar and Stellar Astrophysics · Physics 2022-09-26 Jean-Christophe Pain , Franck Gilleron , Maxime Comet

In this paper, we describe a new hydrodynamics code for 1D and 2D astrophysical simulations, BETHE-hydro, that uses time-dependent, arbitrary, unstructured grids. The core of the hydrodynamics algorithm is an arbitrary Lagrangian-Eulerian…

Astrophysics · Physics 2009-11-13 Jeremiah W. Murphy , Adam Burrows

While many astrophysical plasmas can be modelled successfully assuming ionisation and thermal equilibrium, in some cases this is not appropriate and a non-equilibrium approach is required. In nebulae around evolved stars the local elemental…

Astrophysics of Galaxies · Physics 2025-03-11 Arun Mathew , Jonathan Mackey , Maggie Celeste , Thomas J. Haworth , Garrelt Mellema

This work provides analytical solutions describing the post-shock structure of radiative shocks growing in astrophysics and in laboratory. The equations including a cooling function $\Lambda \propto \rho^{\epsilon} P^{\zeta} x^{\theta}$ are…

(*** abridged ***) Context: The wings of Balmer lines are often used as effective temperature diagnostics for late-type stars under the assumption they form in local thermodynamic equilibrium. Aims: Our goal is to investigate the non-LTE…

Astrophysics · Physics 2009-11-13 P. S. Barklem

We present the implementation of an implicit-explicit (IMEX) Runge-Kutta numerical scheme for general relativistic hydrodynamics coupled to an optically thick radiation field in two existing GR-hydrodynamics codes. We argue that the…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Constanze Roedig , Olindo Zanotti , Daniela Alic

The emergence of three-dimensional magneto-hydrodynamic (MHD) simulations of stellar atmospheres has sparked a need for efficient radiative transfer codes to calculate detailed synthetic spectra. We present RH 1.5D, a massively parallel…

Solar and Stellar Astrophysics · Physics 2015-01-21 Tiago M. D. Pereira , Han Uitenbroek

The spectacular recent development of modern high-energy density laboratory facilities which concentrate more and more energy in millimetric volumes allows the astrophysical community to reproduce and to explore, in millimeter-scale targets…

Solar and Stellar Astrophysics · Physics 2011-03-17 Emeric Falize , Claire Michaut , Serge Bouquet

This paper describes the first steps of development of a new multidimensional time implicit code devoted to the study of hydrodynamical processes in stellar interiors. The code solves the hydrodynamical equations in spherical geometry and…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 M. Viallet , I. Baraffe , R. Walder

Radiation flow through an inhomogeneous medium is critical in a wide range of physics and astronomy applications from transport across cloud layers on the earth to the propagation of supernova blast-waves producing UV and X-ray emission in…

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