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Extragalactic H2 and its variable relation to CO

F. P. Israel
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Abstract

A steep metallicity dependence of the CO-to-H2 conversion factor X of the form log X = 12.2 - 2.5 log[O]/[H], based on a sample of 20 (extra)galactic determinations, is presented and discussed. The apparently less steep dependence found from millimeter interferometer observations is explained within the context of photon-dominated regions.

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F. P. Israel. 2000-01-14. Extragalactic H2 and its variable relation to CO. https://arxiv.org/abs/astro-ph/0001250

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