WW horologii: X-ray and optical observations

Abstract

The eclipsing AM Herculis binary WW Hor (EXO 023432-5232.3) was observed in the X-ray band with the ROSAT satellite and in the optical band with the 3.9-m telescope of the Anglo-Australian Observatory. A clear eclipse is seen in the X-ray light curve of this system for the first time. The relative location of the X-ray eclipse suggests that the accretion pole on the white dwarf surface has migrated in the last few years, consistent with the optical data. The 0.2-2 keV spectrum is well fitted with an absorbed power-law model. There is no indication of a soft blackbody component, although such a component could be masked by the absorption. The X-ray luminosity of the system in the 0.2-2 keV band is 1.0 Show more