ISO-SWS Spectral Characterization of Stars

Abstract

Spectral classification in the infrared is necessary to complete the spectral classification in the visual and to understand the physics and evolution of stars. A major contribution was made by the IRAS Low Resolution Spectrometer, which allowed a characterization of the sources according to both spectral features and general shape of the energy distribution in the 8–22 µ,m (IRAS Science Working group, 1986). However, spectra obtained with the ISO Short Wavelength Spectrometer (SWS) (de Graauw et al. 1996, Kessler et al. 1996) provide the basis for a more complete data-base. Compared with LRS, SWS spectra cover a wider flux range and a wider spectral range 2.4–44.5 µm at a significantly higher spectral resolution. This work is part of an extensive ISO dedicated time program STARTYP1/2, which aims to provide a comprehensive spectral classification scheme of over 700 of the brightest representative infrared sources.