The Slow Nova RR Tel and the Symbiotic Stars

Abstract

The slow nova RR Tel belongs to a group of symbiotic stars which contain in addition to an M type component, a hot dust shell. For symbiotics without dust, infrared photometry shows that the M component is constant in light. For these systems the mass exchange is usually considered to be through the inner Lagrangian point. For the dusty systems it is found that the cool stellar component shows large variations in light. This leads to their identification as Mira variables. For a system such as RR Tel therefore the companion may well be accreting from a general stellar wind from the Mira. RR Tel and similar systems show much stronger radiation from dust than normal Miras. Either an unusually dense stellar wind is needed to produce a system of this kind or such a system produces dust, perhaps in a high density region resulting from the inter-action of the stellar wind with the companion.