Studies of symbiotic stars. IV. IUE-optical-IR observations of AS 360.

Abstract

Observations of the symbiotic star are reported and compared to similar objects to determine the consistent properties of interacting binaries. Absolute spectrophotometry is conducted at the wavelengths 1200-11,100 A, and UBV photometric observations are also taken. AS 360 is found to be an interacting binary made up of a dust-free M 4.0 III with a very hot compact companion, and computations are given for the binary's distance, reddening, nebular density, and characteristics of the emission-line spectrum. The forbidden lines are weak, the ionization conditions are high, and the H I, He I, and He II lines show that self-absorption and high-density effects are insignificant. AS 360 is different from other symbiotic stars but analogous to AS 338, and it is expected that AS 360 will enter a large-amplitude outburst similar to that of AS 338 in the near future.