Long Term Spectroscopic Monitoring of the Brightest Symbiotic Stars (Abstract)

Volume 46 number 2 (2018)

Francois Teyssier

67 Rue Jacques Daviel, Rouen 76100, France; francoismathieu.teyssier@bbox.fr

Abstract

(Abstract only) Symbiotic stars are wide interacting binary systems comprising a cool giant and a hot compact star, mostly a white dwarf, accreting from the giant’s wind. Their orbital periods are hundreds of days (for S-type systems containing a normal giant). The accreting WD represents a strong source of ultraviolet radiation that ionizes a fraction of the wind from the giant and produces a rich emission spectrum. They are strongly variable, according to orbital phase and activity, and can produce various types of outbursts. Symbiotic stars are considered as excellent laboratories for studying a variety of astrophysical problems, such as wind from red giants, accretion—eventually throw a disk—thermonuclear outbursts under a wide range of conditions, collimation of stellar wind, formation of jets, etc. About 50 symbiotic stars in the galaxy are bright enough to be studied by amateur spectroscopy with small telescopes ranging from 8 to 24 inches. We have undergone a long-term monitoring program in the visual range of the brightest symbiotics at a resolution from 500 to 15,000. A part of this program is performed in collaboration with or upon the request of professional teams, feeding several publications at least partially (for instance: T CrB, AG Peg, AG Dra).