Measurements of [O I] λ6300/Hα Line Intensity Ratios for Four O Star H II Regions

Type Journal Article
Names N. R. Hausen, R. J. Reynolds, L. M. Haffner
Publication The Astronomical Journal
Volume 124
Issue 6
Pages 3336-3339
Date December 1, 2002
Library Catalog NASA ADS
Abstract We have used the Wisconsin Hα Mapper facility to measure the [O I] λ6300/Hα line intensity ratios for four O star H II regions: S27 (observation coordinates l=6.3d,b=+23.6d), S252 (l=190.1d,b=+0.6d), S261 (l=194.1d,b=-1.9d), and S264 (l=195.1d,b=-12.0d). We find that the ratios range from 0.0015 to 0.0053. These results are roughly a factor of 10 lower than measured [O I]/Hα ratios in directions that sample the warm ionized component of the interstellar medium. This difference implies a significantly lower hydrogen ionization ratio n(H+)/n(H0) or higher electron temperature in the diffuse ionized gas compared with that in the bright discrete O star H II regions.
Tags ISM: General, ISM: H II Regions, ISM: clouds
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