Collisional excitation of water by hydrogen atoms

Abstract

We present quantum dynamical calculations that describe the rotational excitation of H${}_2$O due to collisions with H atoms. We used a recent, high accuracy potential energy surface, and solved the collisional dynamics with the close-coupling formalism, for total energies up to 12 000 cm${}^{-1}$. From these calculations, we obtained collisional rate coefficients for the first 45 energy levels of both ortho- and para-H${}_2$O and for temperatures in the range T = 5-1500 K. These rate coefficients are subsequently compared to the values previously published for the H${}_2$O / He and H${}_2$O / H${}_2$ collisional systems. It is shown that no simple relation exists between the three systems and that specific calculations are thus mandatory.

References in corpus (17)

• An atomic and molecular database for analysis of submillimetre line observations
• Interstellar water chemistry: from laboratory to observations
• Water in Star-Forming Regions with the Herschel Space Observatory (WISH): Overview of key program and first results
• First detection of water vapor in a pre-stellar core
• Warm water vapour in the sooty outflow from a luminous carbon star
• The far-infrared spectrum of Arp 220
• Interstellar H${}_2$O Masers from J Shocks
• Water vapor toward starless cores: the Herschel view
• On the Validity of Collider-Mass Scaling for Molecular Rotational Excitation
• Physical conditions in shocked regions of Orion from ground-based observations of H_2O
• Quantum Calculation of Inelastic CO Collisions with H: I. rotational quenching of low-lying rotational levels
• Low energy H+CO scattering revisited: CO rotational excitation with new potential surfaces
• The Water Vapor Abundance in Orion KL Outflows
• The water abundance behind interstellar shocks: results from $Herschel$/PACS and $Spitzer$/IRS observations of H${}_2$O, CO, and H${}_2$
• Non--local radiative transfer in strongly inverted masers
• A quantum-mechanical study of rotational transitions in H2 induced by H
• H${}_2$O Maser Pumping: The Effect of Quasi-Resonance Energy Transfer in Collisions between H${}_2$ and H${}_2$O Molecules

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• Some observations about the MOLSCAT
• Weak, extended water vapor emission in the Horsehead nebula
• Collisional Pumping of H${}_2$O and CH${}_3$OH Masers in C-Type Shock Waves