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Cosmic Rays from Regions of Star Formation I. The Carina Complex

Published online by Cambridge University Press:  14 August 2015

T. Montmerle ,
J. A. Paul  and
M. Cassé
T. Montmerle
Affiliation:
Section d'Astrophysique Centre d'Etudes Nucléaires de Saclay, France
J. A. Paul
Affiliation:
Section d'Astrophysique Centre d'Etudes Nucléaires de Saclay, France
M. Cassé
Affiliation:
Section d'Astrophysique Centre d'Etudes Nucléaires de Saclay, France

Extract

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Within the error circle of the COS-B gamma-ray source at ℓ = 288°, b = 0° lies the Carina Nebula, one of the most active regions of star formation known, housing several OB associations and Wolf-Rayet stars (WRS), and perhaps also a supernova remnant (SNR). As a region containing intense mass-losing stars it belongs to the same species as the Rho Oph cloud (but much more active), suggested to be associated with the gamma-ray source at ℓ = 353°, b = +16° (Paul et al., this conference). As a group of OB association linked with a SNR, it belongs to the same species as “SNOB's” (Montmerle, 1979), possibly identified with about half of the COS-B sources. We suggest that the source at ℓ = 288°, b = 0° should be identified with the Carina complex. In this case the source would be at ≃ 2.7 kpc and its gamma-ray luminosity would be ≃ 2.1035 erg s−1. It is suggestive that the nearest aggregate of stars, gas and dust (Rho Oph) and the richest one (Carina) are both in the direction of a gamma-ray source. The Carina complex is noted in particular for the compact star clusters Tr 14, Tr 16 and Cr 228 (Humphreys, 1978), altogether comprising 6 of the 7 O3 stars observed in the Galaxy. It is also remarkable that 3 WRS are associated with the complex. All 3 WRS are of the WN7 type, having the highest mass-loss rate of WRS (≃ 10−4 M⊙ yr−1). Even more remarkable is the presence of the strange Carina object which sheds mass at the extraordinary rate of 10−3 to 0.075 M⊙ yr−1, with a velocity of ≃ 600 km s−1. Moreover, according to radio (Jones, 1973) and optical (Elliot, 1979) data, there seems to be a SNR buried in the Nebula. However, it is not seen at X-ray wavelengths by the Einstein observatory (Seward et al., 1979). This could be explained if the SNR has a luminosity Lx < 1034 erg s−1, since it could then be conceivably hidden by the unstructured, diffuse X-background. The molecular cloud associated with the Carina Nebula has been observed in the lines of H2CO and OH (Dickel, 1974). The cloud has a derived mass of ≲ 105 M⊙, typical of other molecular clouds.

Type
Research Article
Information
Symposium - International Astronomical Union , Volume 94: Origin of Cosmic Rays , 1981 , pp. 321 - 322
Copyright
Copyright © Reidel 1981 

References

Cassé, M. and Paul, J.A. 1980, Ap. J., 237, 236.Google Scholar
Dickel, H.R. 1974, Astr. Ap., 31, 11.Google Scholar
Elliot, K.H. 1979, M.N.R.A.S., 186, 9p.Google Scholar
Humphreys, R.M. 1978, Ap. J. Suppl., 38, 309.Google Scholar
Jones, B.B. 1973, Austr. J. Phys., 26, 545.CrossRefGoogle Scholar
Montmerle, T. 1979, Ap. J., 231, 95.Google Scholar
Montmerle, T. and Cesarsky, C.J. 1980, in “Non Solar Gamma Rays”, eds. Cowsik, R. and Wills, R.D. (Oxford: Pergamon Press), 7.Google Scholar
Seward, F.D. et al. 1979, Ap. J. (Letters), 234, L55.Google Scholar
Wills, R.D. et al. 1980, in “Non Solar Gamma Rays”, eds. Cowsik, R. and Wills, R.D. (Oxford: Pergamon Press), 43.Google Scholar