SPECTRAL CLASSIFICATION OF SYMBIOTIC STARS IN THE NEAR-INFRARED

We present preliminary results of near infrared observations of 6 S ty pe symbiotic binaries, made with the aim of confirming and improving p revious spectral classifications of the cool component. Representative CCD spectra of some symbiotic and comparison stars in the region of t he Ca II infrared triplet are displayed. On our spectrograms at a disp ersion of 33 angstrom/ mm the FeI/Ti II blend at 8469 angstrom and the Fe I line at 8514 angstrom are more useful luminosity discriminants f or symbiotics than the Ca II triplet (8498, 8542 and 8662 angstrom) wh ich is disturbed in some symbiotic spectra by emission components of t he Ca II triplet and of Paschen lines. The temperature classification of late M cool components can be reliably derived from strengths of Ti O and VO bands. Preliminary new spectral types and luminosity classes of six observed symbiotic stars are described and discussed.