Collapse of Low Mass Clouds in the Presence of UV Radiation Field
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چکیده
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 H2 cooling dominates photoheating and the temperature drops to below 10K. Consequently, the mass of the cooled core is evaluated as Mcool = 3.6× 10 6M⊙ (I21/1) −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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تاریخ انتشار 2000