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Session 21 -- Cataclysmic Variables, Dwarf Novae
Display presentation, Monday, 9, 1995, 9:20am - 6:30pm

[21.01] Analysis of EUVE Lightcurves of AM Her Systems

S.B. Howell (PSI), M.M. Sirk (Center for EUV Astrophysics--UC Berkeley), ()

We present EUV lightcurves for a number of AM Her systems observed either as GO targets or with the Right Angle Program. Our data is either from our own GO pointings or from the EUVE archive. We have formed lightcurves for 10 AM Hers and show in our presentation, the similarities and differences present. We draw some conclusions by grouping the systems by inclination, magnetic field strength and other physical parameters. In order to understand the physical structures responsible for these EUV emissions, we have developed a software model to generate synthetic light curves. We find that the EUV accretion regions in the systems UZ For and VV Pup cannot be fit with a flat spot confined to the white dwarf surface, regardless of its shape or brightness profile. Rather, a small, symmeteric raised spot is the only shape consistent with the data. Additionally, we detect a very gradual rise and fall in the EUV flux ($<5\%$ of the peak flux) at phases when the spot is completley obscurred behind the WD limb. We attribute this to emission from the accretion column at distances up to 15\% of the WD radius.

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