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Lyman Continuum Extinction by Dust in H {\sc ii} Regions of Galaxies

Akio K. Inoue
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Abstract

We examine Lyman continuum extinction (LCE) in H II regions by comparing infrared fluxes of 49 H II regions in the Galaxy, M31, M33, and the LMC with estimated production rates of Lyman continuum photons. A typical fraction of Lyman continuum photons that contribute to hydrogen ionization in the H II regions of three spiral galaxies is $\la$ 50 %. The fraction may become smaller as the metallicity (or dust-to-gas ratio) increases. We examine the LCE effect on estimated star formation rates (SFR) of galaxies. The correction factor for the Galactic dust-to-gas ratio is 2-5.

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Akio K. Inoue. 2001-06-28. Lyman Continuum Extinction by Dust in H {\sc ii} Regions of Galaxies. https://doi.org/10.1086/323095

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