UV observations of X-ray sources 2A 0311-227 and 2A 0526-328.

Abstract

IUE satellite observations of the X-ray sources 2A0311-227 and 2A0526-328, which are suspected to be AM Her-type dwarf novae, are reported. Spectra were obtained by the long-wavelength (1900-3200 A) and short-wavelength (110-1900 A) cameras at 10 A resolution over an 8-hr period. The short-wavelength emission lines and continua of 2A0311-227 are found to confirm its identification with the AM Her class, with a continuum consistent with the Rayleigh-Jeans tail of a black body peaking in very soft X rays. The short-wavelength UV spectra of 2A0526-328 are observed to be more similar to that of another dwarf nova, SS Cygni, and suggest that the UV emission arises from an accretion disk, with the entire binary system immersed in a strong wind.