Temperature fluctuations in H II regions: Ionization by cosmic rays as a key mechanism

Bibcode
2005A&A...437L..11G
DOI
10.1051/0004-6361:200500129
Giammanco, C.; Beckman, J. E.
Bibliographical reference

Astronomy and Astrophysics, Volume 437, Issue 1, July I 2005, pp.L11-L14

Advertised on:
7
2005
Journal
Astronomy and Astrophysics
Number of authors
2
IAC number of authors
2
Citations
18
Refereed citations
14
Description
We present a detailed model capable of explaining quantitatively the temperature fluctuations observed in luminous, large H II regions. The model is based on two assumptions which we justify on the basis of observations: that the major fraction of the hydrogen in the clouds that form the H II regions is not photoionized and is essentially H I, this H I is lightly ionized by fluxes of low energy cosmic rays (CR) produced by processes originating in the hot stars which illuminate the regions.
Type
Refereed
Clouds
Methods

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