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arXiv · 2112.09013

How D-type HII region expansion depends on numerical resolution

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

We investigate the resolution dependence of HII regions expanding past their Strömgren spheres. We find that their structure and size, and the radial momentum that they attain at a given time, is in good agreement with analytical expectations if the Strömgren radius is resolved with $dr \leq 0.3\,R_{\rm st}$. If this is not satisfied, the radial momentum may be over- or under-estimated by factors up to 10 or more. Our work has significance for the amount of radial momentum that a HII region can impart to the ambient medium in numerical simulations, and thus on the relative importance of ionizing feedback from massive stars.

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J. M. Pittard, M. M. Kupilas, C. J. Wareing. 2021-12-16. How D-type HII region expansion depends on numerical resolution. https://doi.org/10.1093/mnras%2Fstab3707

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