HEAD 2003 Meeting
Session 46. X-ray Binaries and Cataclysmic Variables II
Oral, Wednesday, March 26, 2003, 9:00-10:00am

[Previous] | [Session 46] | [Next]

[46.05] XMM-Newton Observations of the Dwarf Nova VW Hyi

D. Pandel (UC Santa Barbara), F.A. Cordova, S.B. Howell (IGPP, UC Riverside)

We present our analysis of XMM-Newton data of the dwarf nova VW Hyi obtained during the quiescent state. The X-ray spectrum indicates that the boundary layer is an optically thin plasma with a continuous temperature distribution and a maximum temperature of ~6 keV. The ratio of boundary layer to disk luminosity is fairly low at 0.2. We find that the boundary layer is rotating at a velocity of ~600 km/s, which is similar to the white dwarf's rotation velocity. We detect a 60-s quasi-periodic X-ray oscillation that is possibly connected to the rotation of the boundary layer. A correlation is found between the X-ray and the ultra-violet variability with the X-rays being delayed by ~100 s. An orbital modulation of the X-ray flux suggests a misalignment between the rotation axes of the white dwarf and the inner disk.

[Previous] | [Session 46] | [Next]

Bulletin of the American Astronomical Society, 35#2
© 2003. The American Astronomical Soceity.