English

Stellar sources in the ISOGAL intermediate bulge fields

Astrophysics 2009-11-07 v1

Abstract

We present a study of ISOGAL sources in the "intermediate" galactic bulge (|ll| << 2^\circ, |bb| \sim 1^\circ--4^\circ), observed by ISOCAM at 7 and 15 μm\mu m. In combination with near-infrared (I, J, Ks_{\rm s}) data of DENIS survey, complemented by 2MASS data, we discuss the nature of the ISOGAL sources, their luminosities, the interstellar extinction and the mass-loss rates. A large fraction of the 1464 detected sources at 15 μm\mu m are AGB stars above the RGB tip, a number of them show an excess in ([7]-[15])0_{\rm 0} and (Ks_{\rm s}-[15])0_{\rm 0} colours, characteristic of mass-loss. The latter, especially (Ks_{\rm s}-[15])0_{\rm 0}, provide estimates of the mass-loss rates and show their distribution in the range 108^{-8} to 105^{-5} M_{\rm \odot}/yr.

Keywords

Cite

@article{arxiv.astro-ph/0303137,
  title  = {Stellar sources in the ISOGAL intermediate bulge fields},
  author = {D. K. Ojha and A. Omont and F. Schuller and G. Simon and S. Ganesh and M. Schultheis},
  journal= {arXiv preprint arXiv:astro-ph/0303137},
  year   = {2009}
}

Comments

16 pages, accepted for publication in Astronomy and Astrophysics

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