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Dust-cooling--induced Fragmentation of Low-metallicity Clouds

T. Tsuribe·K. Omukai
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Abstract

Dynamical collapse and fragmentation of low-metallicity cloud cores is studied using three-dimensional hydrodynamical calculations, with particular attention devoted whether the cores fragment in the dust-cooling phase or not. The cores become elongated in this phase, being unstable to non-spherical perturbation due to the sudden temperature decrease. In the metallicity range of 10^{-6}-10^{-5}Z_sun, cores with an initial axis ratio >2 reach a critical value of the axis ratio (>30) and fragment into multiple small clumps. This provides a possible mechanism to produce low-mass stars in ultra-metal-poor environments.

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T. Tsuribe, K. Omukai. 2006-03-17. Dust-cooling--induced Fragmentation of Low-metallicity Clouds. https://doi.org/10.1086/504290

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