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Related papers: Non-equilibrium CO chemistry in the solar atmosphe…

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The role of carbon monoxide as a cooling agent for the thermal structure of the mid-photospheric to low-chromospheric layers of the solar atmosphere in internetwork regions is investigated. The treatment of radiative cooling via spectral…

Astrophysics · Physics 2009-11-11 S. Wedemeyer-Böhm , M. Steffen

CO spectral line formation in the Sun has long been a source of consternation for solar physicists, as have the elemental abundances it seems to imply. We modelled solar CO line formation using a realistic, ab initio, time-dependent 3D…

Astrophysics · Physics 2007-05-23 Patrick C. Scott , Martin Asplund , Nicolas Grevesse , A. Jacques Sauval

Our aim is to determine the dominant processes and timescales for the ionisation equilibrium of calcium under solar chromospheric conditions. The study is based on numerical simulations with the RADYN code, which includes hydrodynamics,…

Solar and Stellar Astrophysics · Physics 2015-05-27 Sven Wedemeyer-Böhm , Mats Carlsson

The ionization state of the gas in the dynamic solar chromosphere can depart strongly from the instantaneous statistical equilibrium commonly assumed in numerical modeling. We improve on earlier simulations of the solar atmosphere that only…

Solar and Stellar Astrophysics · Physics 2016-02-03 Thomas Peter Golding , Jorrit Leenaarts , Mats Carlsson

An accurate treatment of the multiphase interstellar medium (ISM) in hydrodynamic galaxy simulations requires that we follow not only the thermal evolution of the gas, but also the evolution of its chemical state, including its molecular…

Astrophysics of Galaxies · Physics 2015-06-18 Alexander J. Richings , Joop Schaye , Benjamin D. Oppenheimer

Context: Chemical models of dense cloud cores often utilize the so-called pseudo-time-dependent approximation, in which the physical conditions are held fixed and uniform as the chemistry occurs. In this approximation, the initial…

Solar and Stellar Astrophysics · Physics 2015-05-18 G. E. Hassel , E. Herbst , E. A. Bergin

We present new computations of the equilibrium and non-equilibrium cooling efficiencies and ionization states for low-density radiatively cooling gas containing cosmic abundances of the elements H, He, C, N, O, Ne, Mg, Si, S, and Fe. We…

Astrophysics · Physics 2009-11-11 Orly Gnat , Amiel Sternberg

We present a series of hydrodynamic simulations of isolated galaxies with stellar mass of $10^{9} \, \rm{M}_{\odot}$. The models use a resolution of $750 \, \rm{M}_{\odot}$ per particle and include a treatment for the full non-equilibrium…

Astrophysics of Galaxies · Physics 2016-02-17 Alexander J. Richings , Joop Schaye

Emission and absorption lines from elements heavier than helium (metals) represent one of our strongest probes of galaxy formation physics across nearly all redshifts accessible to observations. The vast majority of simulations that model…

Astrophysics of Galaxies · Physics 2022-03-02 Harley Katz

To understand the conditions under which dense, molecular gas is able to form within a galaxy, we post-process a series of three-dimensional galactic-disk-scale simulations with ray-tracing based radiative transfer and chemical network…

The radiation hydrodynamic code CO5BOLD has been supplemented with the time-dependent treatment of chemical reaction networks. Advection of particle densities due to the hydrodynamic flow field is also included. The radiative transfer is…

Astrophysics · Physics 2009-11-10 S. Wedemeyer-Boehm , I. Kamp , J. Bruls , B. Freytag

By using a novel interface between the modern smoothed particle hydrodynamics code GASOLINE2 and the chemistry package KROME, we follow the hydrodynamical and chemical evolution of an isolated galaxy. In order to assess the relevance of…

Astrophysics of Galaxies · Physics 2018-01-24 Pedro R. Capelo , Stefano Bovino , Alessandro Lupi , Dominik R. G. Schleicher , Tommaso Grassi

Starless molecular cores are natural laboratories for interstellar molecular chemistry research. The chemistry of ices in such objects was investigated with a three-phase (gas, surface, and mantle) model. We considered the center part of…

Astrophysics of Galaxies · Physics 2015-04-24 Juris Kalvans

The formation of molecular hydrogen (H$_2$) and carbon monoxide (CO) is sensitive to the volume and column density distribution of the turbulent interstellar medium. In this paper, we study H$_2$ and CO formation in a large set of…

Astrophysics of Galaxies · Physics 2019-01-23 P. R. Joshi , S. Walch , D. Seifried , S. C. O. Glover , S. D. Clarke , M. Weis

We investigate a non-equilibrium ionization state and an electron-ion two-temperature structure of the intracluster medium (ICM) in merging galaxy clusters using a series of N-body and hydrodynamic simulations. Mergers with various sets of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Takuya Akahori , Kohji Yoshikawa

The ionization of hydrogen in the solar chromosphere and transition region does not obey LTE or instantaneous statistical equilibrium because the timescale is long compared with important hydrodynamical timescales, especially of…

Astrophysics · Physics 2009-11-13 J. Leenaarts , M. Carlsson , V. Hansteen , R. J. Rutten

Helium ionization plays an important role in the energy balance of the upper chromosphere and transition region. Helium spectral lines are also often used as diagnostics of these regions. We carry out 1D radiation-hydrodynamics simulations…

Solar and Stellar Astrophysics · Physics 2015-06-18 Thomas Peter Golding , Mats Carlsson , Jorrit Leenaarts

An approximate method for solving the rate equations for the hydrogen populations was extended and implemented in the three-dimensional radiation (magneto-)hydrodynamics code CO5BOLD. The method is based on a model atom with six energy…

Astrophysics · Physics 2009-11-11 Jorrit Leenaarts , Sven Wedemeyer-Boehm

Cold atomic and molecular gas are commonly observed in the winds of both external galaxies and the Milky Way, yet the survival and origin of these cool phases within hot galactic winds is poorly understood. To help gain insight into these…

Chemical equilibrium considerations suggest that, assuming solar elemental abundances, carbon on HD 209458b is sequestered primarily as carbon monoxide (CO) and methane (CH4). The relative mole fractions of CO(g) and CH4(g) in chemical…

Astrophysics · Physics 2008-11-26 Curtis S. Cooper , Adam P. Showman
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