Non--LTE Excitation of H₂ in Magnetised Molecular Shocks

1996/01/08 by I. O'Brien, Ivan O'Brien, O'Brien, Ivan +3
Chemistry · Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Spectroscopy and Laser Applications #astro-ph

paper · pdf · doi:10.48550/arxiv.astro-ph/9601028

Accepted for publication in MNRAS, 5 pages, latex, 6 figures, Compressed postscript also available at http://www.cp.dias.ie/astro/preprints/1996/1.html

arxiv created 1996/01/08 · arxiv updated 2009/12/01

Abstract

The observed H₂ line ratios in OMC--1 and IC443 are not satisfactorily explained by conventional shock excitation models. We consider the microscopic collisional processes implicit in ambipolar diffusion models of magnetised C-shocks and show that non-LTE level populations and emission line ratios are an inevitable consequence of such models. This has important implications for the use of molecular hydrogen lines as diagnostics of shock models in molecular clouds.

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