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arXiv · 2107.14673

How to inflate a wind-blown bubble

J. M. Pittard·C. J. Wareing·M. M. Kupilas
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Abstract

Stellar winds are one of several ways that massive stars can affect the star formation process on local and galactic scales. In this paper we investigate the numerical resolution needed to inflate an energy-driven stellar wind bubble in an external medium. We find that the radius of the wind injection region, $r_{\rm inj}$, must be below a maximum value, $r_{\rm inj,max}$, in order for a bubble to be produced, but must be significantly below this value if the bubble properties are to closely agree with analytical predictions. The final bubble momentum is within 25 per cent of the value from a higher resolution reference model if $\chi = r_{\rm inj}/r_{\rm inj,max}$ = 0.1. Our work has significance for the amount of radial momentum that a wind-blown bubble can impart to the ambient medium in simulations, and thus on the relative importance of stellar wind feedback.

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J. M. Pittard, C. J. Wareing, M. M. Kupilas. 2021-07-30. How to inflate a wind-blown bubble. https://doi.org/10.1093/mnras%2Fstab2712

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