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Related papers: Molecular hydrogen formation in the interstellar m…

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We investigate the formation of molecular hydrogen (H_2) in a primordial H+He gas cloud irradiated by a power-law UV flux. We find that at high densities (>1 cm^{-3}) and low temperatures (<10^4 K), the background radiation enhances the…

Astrophysics · Physics 2009-10-28 Zoltan Haiman , Martin Rees , Abraham Loeb

Molecular outflows contributing to the matter cycle of star forming galaxies are now observed in small and large systems at low and high redshift. Their physical origin is still unclear. In most theoretical studies only warm ionised/neutral…

Astrophysics of Galaxies · Physics 2021-05-28 Philipp Girichidis , Thorsten Naab , Stefanie Walch , Thomas Berlok

Modelling the molecular gas that is routinely detected through CO observations of high-redshift galaxies constitutes a major challenge for ab initio simulations of galaxy formation. We carry out a suite of cosmological hydrodynamic…

Astrophysics of Galaxies · Physics 2020-09-04 Alexander Schäbe , Emilio Romano-Díaz , Cristiano Porciani , Aaron D. Ludlow , Matteo Tomassetti

Understanding the formation of molecules under conditions relevant to interstellar chemistry is fundamental to characterize the chemical evolution of the universe. Using reactive molecular dynamics simulations with model-based or…

Chemical Physics · Physics 2021-06-16 Meenu Upadhyay , Marco Pezzella , Markus Meuwly

Molecular nitrogen is one of the key species in the chemistry of interstellar clouds and protoplanetary disks and the partitioning of nitrogen between N and N2 controls the formation of more complex prebiotic nitrogen-containing species.…

Astrophysics of Galaxies · Physics 2015-06-15 Xiaohu Li , Alan N. Heays , Ruud Visser , Wim Ubachs , Brenton R. Lewis , Stephen T. Gibson , Ewine F. van Dishoeck

OH radicals play a key role as an intermediate in the water formation chemistry of the interstellar medium. For example the reaction of OH radicals with H$_2$ molecules is among the final steps in the astrochemical reaction network starting…

Astrophysics of Galaxies · Physics 2017-08-21 Jan Meisner , Thanja Lamberts , Johannes Kästner

A continuous supersonic flow reactor has been used to measure rate constants for the C + NH3 reaction over the temperature range 50 to 296 K. C atoms were created by the pulsed laser photolysis of CBr4. The kinetics of the title reaction…

To investigate the fundamental principles of H2 formation in a giant molecular cloud (GMC), we derive the HI and H2 surface density (Sigma_HI and Sigma_H2) images of the Perseus molecular cloud on sub-pc scales (~0.4 pc). We use the…

We develop the theory of radiative association of an atom and a diatomic molecule within a close-coupling framework. We apply it to the formation of H$_3^-$ after the low energy collision (below 0.5 eV) of H$_2$ with H$^-$. Using recently…

Atomic Physics · Physics 2015-05-27 M. Ayouz , Raphael Lopes , Maurice Raoult , Olivier Dulieu , V. Kokoouline

Physical conditions within DLAs can reveal the star formation history, determine the chemical composition of the associated ISM, and hence document the first steps in the formation of present day galaxies. Here we present calculations that…

Astrophysics · Physics 2009-09-29 Raghunathan Srianand , Gargi Shaw , Gary Ferland , Patrick Petitjean , Cedric Ledoux

The chemistry along the mass loss of Hot Jupiters is generally considered to be simple, consisting mainly of atoms, prevented from forming more complex species by the intense radiation field from their host stars. In order to probe the…

Earth and Planetary Astrophysics · Physics 2016-01-06 Rafael Pinotti , Heloisa Maria Boechat-Roberty

The first off-lattice Monte Carlo kinetics model of interstellar dust-grain surface chemistry is presented. The positions of all surface particles are determined explicitly, according to the local potential minima resulting from the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Robin T. Garrod

We present an efficient heating/cooling method coupled with chemistry and ultraviolet (UV) radiative transfer, which can be applied to numerical simulations of the interstellar medium (ISM). We follow the time-dependent evolution of…

Astrophysics of Galaxies · Physics 2022-12-28 Jeong-Gyu Kim , Munan Gong , Chang-Goo Kim , Eve C. Ostriker

Grain-surface reactions play an essential role in interstellar chemistry, since dust grain catalyses reactions at its surface allowing for the formation of molecules. We used a chemical model in which both gas-phase and grain-surface…

Astrophysics of Galaxies · Physics 2015-06-19 Laura Reboussin , Valentine Wakelam , Stéphane Guilloteau , Franck Hersant

It is a fact that interstellar formation processes are thermodynamically affected. Based on this, the seven heterocycles; imidazole, pyridine, pyrimidine, pyrrole, quinoline, isoquinoline and furan that have been searched for from different…

Astrophysics of Galaxies · Physics 2021-09-08 Emmanuel E. Etim , ROA Adelagun , Chrysanthus Andrew , Oladimeji Enock Oluwole

The desorption of molecular species from ice mantles back into the gas phase in molecular clouds results from a variety of very poorly understood processes. We have investigated three mechanisms; desorption resulting from H_2 formation on…

Astrophysics · Physics 2009-11-13 J. F. Roberts , J. M. C. Rawlings , S. Viti , D. A. Williams

Formamide has a key role in prebiotic chemistry as it is the simplest molecule containing the four most important atoms from a biological point of view: hydrogen, carbon, nitrogen and oxygen. Due to its importance, the formation of this…

Chemical Physics · Physics 2021-11-02 Berta Martínez-Bachs , Albert Rimola

We present a sub-grid model for star formation in galaxy simulations, incorporating molecular hydrogen ($\mathrm{H}_2$) production via dust grain condensation and its destruction through star formation and photodissociation. Implemented…

Astrophysics of Galaxies · Physics 2025-10-02 E. Lozano , C. Scannapieco , S. E. Nuza , Y. Ascasibar , V. Springel

We present a computational study into the adsorption properties of CO$_2$ on amorphous and crystalline water surfaces under astrophysically relevant conditions. Water and carbon dioxide are two of the most dominant species in the icy…

Astrophysics of Galaxies · Physics 2017-09-13 L. J. Karssemeijer , G. A. de Wijs , H. M. Cuppen

We have used archival far-ultraviolet spectra from observations made by HST/STIS and FUSE to determine the column densities and rotational excitation temperatures for CO and H2, respectively, along the lines of sight to 23 Galactic O and B…

Astrophysics · Physics 2009-01-19 Eric B. Burgh , Kevin France , Stephan R. McCandliss
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