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Optical HII regions

Published online by Cambridge University Press:  14 August 2015

Y. M. Georgelin ,
Y. P. Georgelin  and
J.-P. Sivan
Y. M. Georgelin
Affiliation:
Observatoire de Marseille and Laboratorie d'Astronomie Spatiale, Marseille, France
Y. P. Georgelin
Affiliation:
Observatoire de Marseille and Laboratorie d'Astronomie Spatiale, Marseille, France
J.-P. Sivan
Affiliation:
Observatoire de Marseille and Laboratorie d'Astronomie Spatiale, Marseille, France

Extract

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The ionized hydrogen regions seen on monochromatic Hα photographs of nearby spiral galaxies (e.g. Fig. 1) can be divided into four classes (Monnet, 1971): (1) bright, condensed, classical HII regions; (2) diffuse emission in the arms surrounding and connecting the classical regions (emission measure (EM) ∼ 150 cm−6 pc, for a gas electron temperature of 6000 K); (3) much fainter, diffuse emission extending over the entire disk (EM ∼ 50 cm−6 pc) in most Sc and Sd galaxies; (4) diffuse emission in the nuclear region.

Type
II. THE DISK COMPONENT
Information
Symposium - International Astronomical Union , Volume 84: The Large-Scale Characteristics of the Galaxy , 1979 , pp. 65 - 72
Copyright
Copyright © Reidel 1979 

References

Boulesteix, J., Courtès, G., Laval, A., Monnet, G., Petit, H.: 1974, Astron. Astrophys. 37, 33.Google Scholar
Comte, G., Monnet, G.: 1974, Astron. Astrophys. 33, 161.Google Scholar
Courtès, G., Saïsse, M., Sivan, J-P.: 1978 (in preparation) Google Scholar
Crampton, D., Georgelin, Y.M.: 1975, Astron. Astrophys. 40, 317.Google Scholar
Crampton, D., Georgelin, Y.M., Georgelin, Y.P.: 1978, Astron. Astrophys. 66, 1.Google Scholar
de Vaucouleurs, G.: 1978, Astrophys. J. (in press) Google Scholar
Georgelin, Y.M., Georgelin, Y.P.: 1976, Astron. Astrophys. 49, 57.Google Scholar
Gum, C.S., de Vaucouleurs, G.: 1953, Observatory 73, 152.Google Scholar
Monnet, G.: 1971, Astron. Astrophys. 12, 379.Google Scholar
Reynolds, R.J.: 1976, Astrophys. J. 203, 151.Google Scholar
Reynolds, R.J., Roesler, F.L., Scherb, F.: 1974, Astrophys. J. Letters 192, L53.Google Scholar
Reifenstein, E.C., Wilson, T.L., Burke, B.F., Mezger, P.G., Altenhoff, W.F.: 1970, Astron. Astrophys. 4, 357.Google Scholar
Sivan, J-P.: 1974, Astron. Astrophys. Suppl. 16, 163.Google Scholar
Sivan, J-P.: 1977, , Google Scholar
Torres-Peimbert, S., Lazcano-Araujo, A., Peimbert, M.: 1974, Astrophys. J. 191, 401.Google Scholar
Wilson, T.L., Mezger, P.G., Gardner, F.F., Milne, D.K.: 1970, Astron. Astrophys. 6, 364.Google Scholar