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arXiv · 2301.12300

Molecular gas properties in young stellar clusters with a suppressed star cluster wind

Sergiy Silich·Jean Turner·Jonathan Mackey·Sergio Martinez-Gonzalez
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Abstract

In compact and dense star-forming clouds a global star cluster wind could be suppressed. In this case the stellar feedback is unable to expel the leftover gas from the cluster. Young massive stars remain embedded into a dense residual gas and stir it moving in the gravitational well of the system. Here we present a self-consistent model for the molecular gas distribution in such young, enshrouded stellar clusters. It is assumed that the cloud collapse terminates and the star formation ceases when a balance between the turbulent pressure and gravity and between the turbulent energy dissipation and regeneration rates is established. These conditions result in an equation that determines the residual gas density distribution that, in turn, allows one to determine the other characteristics of the leftover gas and the star formation efficiency. It is shown that model predictions are in good agreement with several observationally determined properties of cloud D1 in nearby dwarf spheroidal galaxy NGC 5253 and its embedded cluster.

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Sergiy Silich, Jean Turner, Jonathan Mackey, Sergio Martinez-Gonzalez. 2023-01-28. Molecular gas properties in young stellar clusters with a suppressed star cluster wind. https://doi.org/10.3847/2041-8213/acb687

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