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, K_s 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.