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Scattered Light in H II Regions

Published online by Cambridge University Press:  08 February 2017

C. R. O'Dell*
Affiliation:
Yerkes Observatory Williams Bay, Wisconsin

Extract

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The Possible Role of Interstellar Particles in the determination of the ionization structure of H II regions, the transfer of the Lyman line radiation, and the early stages of stellar contraction have stimulated an investigation of the properties and relative abundance of the scattering particles that exist within the boundaries of a number of bright galactic diffuse nebulae. It is interesting to note that the conclusion reached in reference 1, based on crude observations, was that there does not seem to be any scattered light in the bright H II regions; this conclusion is in contradiction to the results of the study presented herein. Results of the present investigation show that, in general, dust is an important constituent of the diffuse nebulae; that certain anomalies in the gas-to-dust ratio can be explained in a straightforward manner through the interaction of the particles and stellar radiation; and that the anomalies are closely related to the deviations known to exist in the interstellar reddening law.

Type
Research Article
Copyright
Copyright © Kluwer Academic Publishers 1965

References

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