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On the Thermal Instability in a Contracting Gas Cloud and Formation of a Bound Cluster

Motomichi Tashiro·Ryoichi Nishi
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Abstract

We perform linear analysis of thermal instability in a contracting large cloud filled with warm HI gas and investigate the effect of metallicity and radiation flux. When the cloud reaches critical density n_f, the cloud fragments into cool, dense condensations because of thermal instability. For a lower metallicity gas cloud, the value of n_f is high. Collision between condensations will produce self-gravitating clumps and stars thereafter. From the result of calculation, we suggest that high star formation efficiency and bound cluster formation are realized in low-metallicity and/or strong-radiation environments.

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Motomichi Tashiro, Ryoichi Nishi. 2000-05-17. On the Thermal Instability in a Contracting Gas Cloud and Formation of a Bound Cluster. https://doi.org/10.1086/308917

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