Leaky H II Regions and Heliumionization in the Reynolds Layer
作者： K. Wood , J. S. Mathis
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摘要: In the Milky Way’s diffuse ionized gas, helium is observed to be underionized relative hydrogen, implying ionization by a softer radiation field than typical of H ii regions. We construct 3D photoionization models gas and show that ionizing spectra escaping from leaky regions can provide solution He+/H+ problem. Depending on spectral type source(s) fractional leakage region, we find are harder have their He-ionizing photon luminosity supressed. Such yield reduced fraction increased heating compared normal stellar spectra.
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