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

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Carbonyl sulfide (OCS) is an abundant sulfur (S)-bearing species in the interstellar medium. It is present not only in the gas phase, but also on interstellar grains as a solid; therefore, OCS very likely undergoes physicochemical processes…

Astrophysics of Galaxies · Physics 2021-12-02 Thanh Nguyen , Yasuhiro Oba , W. M. C. Sameera , Akira Kouchi , Naoki Watanabe

Context. Carbon monoxide (CO) has been detected in all Giant Planets and its origin is both internal and external in Jupiter and Neptune. Despite its first detection in Uranus a decade ago, the magnitude of its internal and external sources…

Earth and Planetary Astrophysics · Physics 2015-06-17 T. Cavalié , R. Moreno , E. Lellouch , P. Hartogh , O. Venot , G. S. Orton , C. Jarchow , T. Encrenaz , F. Selsis , F. Hersant , L. N. Fletcher

The $^{13}$CO molecule is often used as a column density tracer in regions where the $^{12}$CO emission saturates. The $^{13}$CO column density is then related to that of $^{12}$CO by a uniform isotopic ratio. A similar approximation is…

Astrophysics of Galaxies · Physics 2016-04-25 László Szűcs , Simon C. O. Glover , Ralf S. Klessen

We review our current knowledge of the solar chemical composition as determined from photospheric absorption lines. In particular we describe the recent significant revisions of the solar abundances as a result of the application of a…

Astrophysics · Physics 2015-06-24 Martin Asplund , Nicolas Grevesse , Jacques Sauval

Modelling carbon monoxide (CO) line radiation is computationally expensive for traditional numerical solvers, especially when applied to complex, three-dimensional stellar atmospheres. We present COEmuNet, a 3D convolutional neural network…

Instrumentation and Methods for Astrophysics · Physics 2025-07-16 Shiqi Su , Frederik De Ceuster , Jaehoon Cha , Mark I. Wilkinson , Jeyan Thiyagalingam , Jeremy Yates , Yi-Hang Zhu , Jan Bolte

Interstellar complex organic molecules (iCOMs) can be loosely defined as chemical compounds with at least six atoms in which at least one is carbon. The observations of iCOMs in star-forming regions have shown that they contain an important…

Solar and Stellar Astrophysics · Physics 2019-09-30 Joan Enrique-Romero , Albert Rimola , Cecilia Ceccarelli , Piero Ugliengo , Nadia Balucani , Dimitrios Skouteris

We present the first detection in space of O-protonated carbonyl sulfide (\ch{HOCS+}), in the midst of an ultradeep molecular line survey toward the G+0.693-0.027 molecular cloud. From the observation of all $K$$_a$ = 0 transitions ranging…

We measure the CO-to-H$_2$ conversion factor ($\alpha_\mathrm{CO}$) in 37 galaxies at 2~kpc resolution, using dust surface density inferred from far-infrared emission as a tracer of the gas surface density and assuming a constant…

Red-shifted components of chromospheric emission lines in the hard X-ray impulsive phase of solar flares have recently been studied through their 30 s evolution with the high resolution of IRIS. Radiative-hydrodynamic flare models show that…

We investigate molecular evolution from a molecular cloud core to a first hydrostatic core in three spatial dimensions. We perform a radiation hydrodynamic simulation in order to trace fluid parcels, in which molecular evolution is…

Solar and Stellar Astrophysics · Physics 2015-06-05 Kenji Furuya , Yuri Aikawa , Kengo Tomida , Tomoaki Matsumoto , Kazuya Saigo , Kohji Tomisaka , Franck Hersant , Valentine Wakelam

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

Context. The solar chromosphere is the interface between the solar surface and the solar corona. Modelling of this region is difficult because it represents the transition from optically thick to thin radiation escape, from gas-pressure…

Solar and Stellar Astrophysics · Physics 2015-12-09 Mats Carlsson , Viggo H. Hansteen , Boris V. Gudiksen , Jorrit Leenaarts , Bart De Pontieu

CHROMIS, a new imaging spectrometer at the Swedish 1-m Solar Telescope (SST), can observe the chromosphere in the H and K lines of Ca II at high spatial and spectral resolution. Accurate modeling as well as an understanding of the formation…

The photo-induced desorption and oxidation of CO on Ru(0001) is simulated using ab initio molecular dynamics with electronic friction that accounts for the non-equilibrated excited electrons and phonons. Different (O,CO) coverages are…

Materials Science · Physics 2023-07-06 Auguste Tetenoire , J. Iñaki Juaristi , Maite Alducin

The solar photospheric oxygen abundance is still widely debated. Adopting the solar chemical composition based on the "low" oxygen abundance, as determined with the use of three-dimensional (3D) hydrodynamical model atmospheres, results in…

Solar and Stellar Astrophysics · Physics 2016-08-08 M. Steffen , D. Prakapavičius , E. Caffau , H. -G. Ludwig , P. Bonifacio , R. Cayrel , A. Kučinskas , W. C. Livingston

Recent experiments revealed an anomalous dependence of carbon monoxide oxidation at Ru(0001) on oxygen pressure and a particularly high reaction rate. Below we report density functional theory calculations of the energetics and reaction…

Materials Science · Physics 2009-10-30 C. Stampfl , M. Scheffler

Isocyanic acid (HNCO), the most stable of the simplest molecules containing the four main elements essential for organic chemistry, has been observed in several astrophysical environments such as molecular clouds, star-forming regions,…

Chemical networks used for models of interstellar clouds contain many reactions, some of them with poorly determined rate coefficients and/or products. In this work, we report a method for improving the predictions of molecular abundances…

Astrophysics of Galaxies · Physics 2009-11-13 Valentine Wakelam , Jean-Christophe Loison , Eric Herbst , Dahbia Talbi , Dongui Quan , Françoise Caralp

The formation of CO2 in quiescent regions of molecular clouds is not yet fully understood, despite CO2 having an abundance of around 10-34 % H2O. We present a study of the formation of CO2 via the non-energetic route CO + OH on non-porous…

Solar and Stellar Astrophysics · Physics 2011-07-05 Jennifer Anna Noble , François Dulieu , Emanuele Congiu , Helen Jane Fraser

We report the presence of a systematic excess in the molecular hydrogen fraction ($f_{\mathrm{H2}} = 2 \, n_{\mathrm{H2}}/n_{\mathrm{H}}$) in studies that use a reduced chemistry network to calculate $f_{\mathrm{H2}}$ of gas with a non-zero…

Astrophysics of Galaxies · Physics 2026-03-03 Sylvia Ploeckinger