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Related papers: Carbon monoxide in the solar atmosphere I. Numeric…

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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

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

The use of hydrodynamical simulations, the selection of atomic data, and the computation of deviations from local thermodynamical equilibrium for the analysis of the solar spectra have implied a downward revision of the solar metallicity.…

Solar and Stellar Astrophysics · Physics 2015-05-18 E. Caffau , H. -G. Ludwig , P. Bonifacio , R. Faraggiana , M. Steffen , B. Freytag , I. Kamp , T. R. Ayres

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

Carbon monoxide (CO) is the most abundant molecule after molecular hydrogen and is important for the chemistry in circumstellar envelopes around evolved stars. When modelling the strength and shape of molecular lines, the size of the CO…

Solar and Stellar Astrophysics · Physics 2021-06-02 Martin Groenewegen , Maryam Saberi

Carbon monoxide (CO) emission has been observed in a number of core-collapse supernovae (SNe) and is known to be an important coolant at late times. We have implemented a chemical reaction network in the radiative-transfer code CMFGEN to…

Solar and Stellar Astrophysics · Physics 2024-06-28 Collin McLeod , D. John Hillier , Luc Dessart

Three-dimensional numerical simulations with CO5BOLD, a new radiation hydrodynamics code, result in a dynamic, thermally bifurcated model of the non-magnetic chromosphere of the quiet Sun. The 3-D model includes the middle and low…

Solar observations of carbon monoxide (CO) indicate the existence of lower-temperature gas in the lower solar chromosphere. We present an observation of pores, and quiet-Sun, and network magnetic field regions with CO 4.66 {\mu}m lines by…

Solar and Stellar Astrophysics · Physics 2023-01-18 Yongliang Song , Xianyong Bai , Xu Yang , Wenda Cao , Han Uitenbroek , Yuanyong Deng , Xin Li , Xiao Yang , Mei Zhang

Binary molecules such as CO, OH, CH, CN, and C$_2$ are often used as abundance indicators in stars. These species are usually assumed to be formed in chemical equilibrium. The time-dependent effects of hydrodynamics can affect the formation…

Solar and Stellar Astrophysics · Physics 2023-07-19 S. A. Deshmukh , H. -G. Ludwig

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

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

Context: The thermal and chemical structures of the upper atmospheres of planets crucially influence losses to space and must be understood to constrain the effects of losses on atmospheric evolution. Aims: We develop a 1D first-principles…

Earth and Planetary Astrophysics · Physics 2018-09-26 Colin P. Johnstone , Manuel Güdel , Helmut Lammer , Kristina G. Kislyakova

Theoretical and observational investigations have indicated that the abundance of carbon monoxide (CO) is very sensitive to intrinsic properties of the gaseous medium, such as density, metallicity, and the background UV field. In order to…

Astrophysics of Galaxies · Physics 2015-05-20 Rahul Shetty , Simon C. Glover , Cornelis P. Dullemond , Ralf S. Klessen

Combining the co-evolving chemistry, hydrodynamics and radiative transfer is an important step for star formation studies. It allows both a better link to observations and a self-consistent monitoring of the magnetic dissipation in the…

Astrophysics of Galaxies · Physics 2016-05-27 Natalia Dzyurkevich , Benoît Commerçon , Pierre Lesaffre , Dimitry Semenov

Carbon monoxide (CO) is the second most abundant molecule in the gas-phase of the interstellar medium. In dense molecular clouds, it is also present in the solid-phase as a constituent of the mixed water-dominated ices covering dust grains.…

Investigating the reliability of the assumption of instantaneous chemical equilibrium (ICE) for calculating the CO number density in the solar atmosphere is of crucial importance for the resolution of the long-standing controversy over the…

Astrophysics · Physics 2009-11-07 A. Asensio Ramos , J. Trujillo Bueno , M. Carlsson , J. Cernicharo

A solar photospheric "thermal profiling" analysis is presented, exploiting the infrared rovibrational bands of carbon monoxide (CO) as observed with the McMath-Pierce Fourier transform spectrometer (FTS) at Kitt Peak, and from above the…

Astrophysics · Physics 2009-11-11 Thomas R. Ayres , Claude Plymate , Christoph U. Keller

(Abridged) Context. With the Herschel Space Observatory, lines of simple molecules (C+, O, and CO) have been observed in the atmosphere of protoplanetary disks. When combined with ground-based [CI], all principle forms of carbon can be…

Solar and Stellar Astrophysics · Physics 2015-06-03 Simon Bruderer , Ewine F. van Dishoeck , Steven D. Doty , Gregory J. Herczeg

We explore CO-CH4 quench kinetics in the atmospheres of substellar objects using updated time-scale arguments, as suggested by a thermochemical kinetics and diffusion model that transitions from the thermochemical-equilibrium regime in the…

Earth and Planetary Astrophysics · Physics 2015-05-28 Channon Visscher , Julianne I. Moses

The solar abundances have undergone a major downward revision in the last decade, reputedly as a result of employing 3D hydrodynamical simulations to model the inhomogeneous structure of the solar photosphere. The very low oxygen abundance…

Solar and Stellar Astrophysics · Physics 2009-10-27 E. Caffau , H. -G. Ludwig , M. Steffen
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