We present a 904-1183 A spectrum of the dwarf nova VW Hydri taken with the
Far Ultraviolet Spectroscopic Explorer during quiescence, eleven days after a
normal outburst, when the underlying white dwarf accreter is clearly exposed in
the far ultraviolet. However, model fitting show that a uniform temperature
white dwarf does not reproduce the overall spectrum, especially at the shortest
wavelengths. A better approximation to the spectrum is obtained with a model
consisting of a white dwarf and a rapidly rotating ``accretion belt''. The
white dwarf component accounts for 83% of the total flux, has a temperature of
23,000K, a v sin i = 400 km/s, and a low carbon abundance. The best-fit
accretion belt component accounts for 17% of the total flux, has a temperature
of about 48,000-50,000K, and a rotation rate Vrot sin i around 3,000-4,000
km/s. The requirement of two components in the modeling of the spectrum of VW
Hyi in quiescence helps to resolve some of the differences in interpretation of
ultraviolet spectra of VW Hyi in quiescence. However, the physical existence of
a second component (and its exact nature) in VW Hyi itself is still relatively
uncertain, given the lack of better models for spectra of the inner disk in a
quiescent dwarf nova.Comment: 6 figures, 10 printed page in the journal, to appear in APJ, 1 Sept.
2004 issue, vol. 61