SPECTRAL CLASSIFICATIONS IN THE COMPOSITE SPECTRA .2. STUDY OF A SAMPLE OF 180 STARS

A sample of 180 supposedly composite-spectrum stars has been studied o n the basis of spectra obtained in the near infrared (8370 - 8780 Angs trom) at a dispersion of 33 Angstrom/mm. The objective was to study th e cooler components of the systems. Of our sample, 120 are true compos ite spectra, 35 are hot spectra of types B, F and 25 are Am stars. We find a strong concentration of the cooler components of the composite spectra around G8III. In view of the difficulty of classifying composi te spectra, because of the superposition of an early type dwarf and a late type giant or supergiant spectrum, we have made several tests to control the classification based upon the infrared region. Since all t ests gave positive results, we conclude that our classifications can b e considered as being both reliable and homogeneous.(1).