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Collapse of Low Mass Clouds in the Presence of UV Radiation Field

Hajime Susa·Tetsu Kitayama
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Abstract

The collapse of marginally Jeans unstable primordial gas clouds in the presence of UV radiation field is discussed. Assuming that the dynamical collapse proceeds approximately in an isothermal self-similar fashion, we investigate the thermal evolution of collapsing central core until H$_2$ cooling dominates photoheating and the temperature drops to below $10^4$K. Consequently, the mass of the cooled core is evaluated as $M_{cool}=3.6\times 10^6 M_\odot(I_{21}/1)^{-0.32}$. This scale depends only on the incident UV intensity, and provides a lower limit to the mass of collapsed objects in the UV radiation field.

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Hajime Susa, Tetsu Kitayama. 2000-04-21. Collapse of Low Mass Clouds in the Presence of UV Radiation Field. https://doi.org/10.1046/j.1365-8711.2000.03616.x

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