English
Related papers

Related papers: A simple model for molecular hydrogen chemistry co…

200 papers

Comparison is made between a number of independent computer programs for radiative transfer in molecular rotational lines. The test models are spherically symmetric circumstellar envelopes with a given density and temperature profile. The…

Roaming has been proposed as a possible mechanism contributing to molecular dissociation in which the fragments can move around one another at relatively large intermolecular distances before separating entirely. While roaming, there is…

We use our variable Eddington tensor (VET) radiation hydrodynamics code to perform two-dimensional simulations to study the impact of radiation forces on atmospheres composed of dust and gas. Our setup closely follows that of Krumholz &…

Astrophysics of Galaxies · Physics 2015-06-19 Shane W. Davis , Yan-Fei Jiang , James M. Stone , Norman Murray

We present a new set of analytic models for the expansion of HII regions powered by UV photoionisation from massive stars and compare them to a new suite of radiative magnetohydrodynamic simulations of turbulent, self-gravitating molecular…

Astrophysics of Galaxies · Physics 2016-06-08 Sam Geen , Patrick Hennebelle , Pascal Tremblin , Joakim Rosdahl

In this study, we present and validate a variation of recently-developed physically motivated sub-grid prescriptions for supernova feedback that account for the unresolved energy-conserving phase of the bubble expansion. Our model builds…

Astrophysics of Galaxies · Physics 2019-01-21 Alessandro Lupi

In our recent papers (Kereslidze et all 2019a, 2021) a non-standard quasi-molecular mechanism was suggested and applied to treat the cosmological recombination. It was assumed that in the pre-recombination stage of evolution of the Universe…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-26 Tamaz Kereselidze , Irakli Noselidze

We describe similarity solutions that characterize the collapse of collisional gas onto scalefree perturbations in an Einstein-de Sitter universe. We consider the effects of radiative cooling and derive self-similar solutions under the…

Astrophysics · Physics 2009-10-31 M. G. Abadi , R. G. Bower , J. F. Navarro

A new, more comprehensive model of gas-grain chemistry in hot molecular cores is presented, in which nondiffusive reaction processes on dust-grain surfaces and in ice mantles are implemented alongside traditional diffusive surface/bulk-ice…

Astrophysics of Galaxies · Physics 2022-02-23 Robin T. Garrod , Mihwa Jin , Kayla A. Matis , Dylan Jones , Eric R. Willis , Eric Herbst

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 simulation of the cosmic evolution of the atomic and molecular phases of the cold hydrogen gas in about 3e7 galaxies, obtained by post-processing the virtual galaxy catalog produced by (De Lucia et al. 2007) on the Millennium…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 D. Obreschkow , D. Croton , G. De Lucia , S. Khochfar , S. Rawlings

The interaction of ionizing and far-ultraviolet radiation with the interstellar medium is of great importance. It results in the formation of regions in which the gas is ionized, beyond which are photodissociation regions (PDRs) in which…

Astrophysics of Galaxies · Physics 2015-10-21 T. G. Bisbas , T. J. Haworth , M. J. Barlow , S. Viti , T. J. Harries , T. Bell , J. A. Yates

We have been constructed a brand-new radiation hydrodynamics solver based upon Smoothed Particle Hydrodynamics (SPH), which works on parallel computer system. The code is designed to investigate the formation and evolution of the first…

Astrophysics · Physics 2015-06-24 Hajime Susa

We present the first 3D Monte Carlo (MC) photoionisation code to include a fully self-consistent treatment of dust radiative transfer (RT) within a photoionised region. This is the latest development (Version 2.0) of the gas-only…

Astrophysics · Physics 2009-11-13 B. Ercolano , M. J. Barlow , P. J. Storey

A mixed quantum-classical approach to simulate the coupled dynamics of electrons and nuclei in nanoscale molecular systems is presented. The method relies on a second order expansion of the Lagrangian in time-dependent density functional…

Chemical Physics · Physics 2009-11-10 T. A. Niehaus , D. Heringer , B. Torralva , Th. Frauenheim

Solar flares involve complex processes that are coupled and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present results from simulations that…

Solar and Stellar Astrophysics · Physics 2015-11-18 Fatima Rubio da Costa , Wei Liu , Vahe' Petrosian , Mats Carlsson

Context. In dense clouds, hydrogenation reactions on icy dust grains are key in the formation of molecules, like formaldehyde, methanol, and complex organic molecules (COMs). These species form through the sequential hydrogenation of CO…

Solar and Stellar Astrophysics · Physics 2018-09-28 K. -J. Chuang , G. Fedoseev , D. Qasim , S. Ioppolo , E. F. van Dishoeck , H. Linnartz

We describe a module for the Athena code that solves the gray equations of radiation hydrodynamics (RHD), based on the first two moments of the radiative transfer equation. We use a combination of explicit Godunov methods to advance the gas…

Instrumentation and Methods for Astrophysics · Physics 2013-06-06 M. Aaron Skinner , Eve C. Ostriker

The recently proposed Hamiltonian Adaptive Resolution Scheme (H-AdResS) allows to perform molecular simulations in an open boundary framework. It allows to change on the fly the resolution of specific subset of molecules (usually the…

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

This work presents a detailed description of the thermochemical non-equilibrium dissociation of diatomic molecules, and applies this theory to the case of $\rm H_2$ dissociation. The master equations are used to derive corresponding…

Chemical Physics · Physics 2025-01-06 Alex T. Carroll , Jacob Wolmer , Guillaume Blanquart , Aaron M. Brandis , Brett A. Cruden