H$_{2}$O Maser Pumping: The Effect of Quasi-Resonance Energy Transfer in Collisions between H$_2$ and H$_2$O Molecules

A. V. Nesterenok; D. A. Varshalovich

doi:10.1134/s1063773714070068

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arXiv · 1407.3135

H$_{2}$O Maser Pumping: The Effect of Quasi-Resonance Energy Transfer in Collisions between H$_2$ and H$_2$O Molecules

A. V. Nesterenok·D. A. Varshalovich

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Abstract

The effect of quasi-resonance energy transfer in collisions between H$_2$ and H$_2$O molecules in H$_2$O maser sources is investigated. New data on the state-to-state rate coefficients for collisional transitions for H$_2$O and H$_2$ molecules are used in the calculations. The results of ortho-H$_2$O level population inversion calculations for the 22.2-, 380-, 439-, and 621-GHz transitions are presented. The ortho-H$_2$O level population inversion is shown to depend significantly on the population distribution of the para-H$_2$ $J = 0$ and $2$ rotational levels. The possibility of quasi-resonance energy transfer in collisions between H$_2$ molecules at highly excited rotational-vibrational levels and H$_2$O molecules is considered. The quasi-resonance energy transfer effect can play a significant role in pumping H$_2$O masers in the central regions of active galactic nuclei and in star-forming regions.

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A. V. Nesterenok, D. A. Varshalovich. 2014-07-11. H$_{2}$O Maser Pumping: The Effect of Quasi-Resonance Energy Transfer in Collisions between H$_2$ and H$_2$O Molecules. https://doi.org/10.1134/s1063773714070068

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