AAVSO: American Association of Variable Star Observers

Spectrophotometry of Symbiotic Stars (Abstract)

Volume 45 number 2 (2017)

David Boyd
5 Silver Lane, West Challow, Wantage, OX12 9TX, United Kingdom; davidboyd@orion.me.uk

Abstract

(Abstract only) Symbiotic stars are fascinating objects—complex binary systems comprising a cool red giant star and a small hot object, often a white dwarf, both embedded in a nebula formed by a wind from the giant star. UV radiation from the hot star ionizes the nebula, producing a range of emission lines. These objects have composite spectra with contributions from both stars plus the nebula and these spectra can change on many timescales. Being moderately bright, they lend themselves well to amateur spectroscopy. This paper describes the symbiotic star phenomenon, shows how spectrophotometry can be used to extract astrophysically useful information about the nature of these systems, and gives results for three symbiotic stars based on the author’s observations.