On the Thermal Instability in a Contracting Gas Cloud and Formation of a Bound Cluster
نویسندگان
چکیده
We perform linear analysis of thermal instability in a contracting large cloud filled with warm H I 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. Subject headings: galaxies: star clusters — globular clusters: general — instabilities
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