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Clumpy ultracompact HII regions -- III. Cometary morphologies around stationary stars

R. J. R. Williams·J. E. Dyson·M. P. Redman
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Abstract

Cometary ultracompact HII regions have been modelled as the interaction of the hypersonic wind from a moving star with the molecular cloud which surrounds the star. We here show that a similar morphology can ensue even if the star is stationary with respect to the cloud material. We assume that the HII region is within a stellar wind bubble which is strongly mass loaded: the cometary shape results from a gradient in the distribution of mass loading sources. This model circumvents problems associated with the necessarily high spatial velocities of stars in the moving star models.

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R. J. R. Williams, J. E. Dyson, M. P. Redman. 1996-03-01. Clumpy ultracompact HII regions -- III. Cometary morphologies around stationary stars. https://doi.org/10.1093/mnras/280.3.667

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