Spectroscopic observations of first ISOGAL sources

Abstract

Infrared Space Observatory Galactic (ISOGAL) survey at 7 and 15 μm of ~ 22 deg2 of the inner galactic disk and bulge, has detected several hundred thousand sources. Combining ISOGAL survey with I, J, H, Ks data of DENIS (Deep Near Infrared Survey of the Southern Sky) and 2MASS (The Two Micron All Sky Survey), has provided a completely new insight of infrared galactic stars. We have proposed a limited preliminary program of low resolution spectroscopy with the 2.3-meter telescope of VBO (Vainu Bappu Observatory, Kavalur, India) on ISOGAL sources, with the double purpose : i) confirm or help to establish the criteria of identification from ISOGAL+DENIS/2MASS data of a few classes of important sources (subclasses of dusty AGB stars, dusty young stars, extreme red giants, supergiants, etc). ii) observe a number of stars which look peculiar. In this paper, we present the spectra of a few sources observed in 6 ISOGAL fields.