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A Far Ultraviolet Study of the Hot White Dwarf in the Dwarf Nova WW Ceti

P. Godon·L. Seward·E. M. Sion·P. Szkody
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Abstract

We present a synthetic spectral analysis of IUE archival and FUSE FUV spectra of the peculiar dwarf nova WW Ceti. During the quiescence of WW Ceti, a white dwarf with Twd=26,000K can account for the FUV flux and yields the proper distance. However, the best agreement with the observations is provided by a two-temperature white dwarf model with a cooler white dwarf at Twd=25,000K providing 75% of the FUV flux and a hotter region (accretion belt or optically thick disk ring) with T=40,000K contributing 25% of the flux for the proper distance. We find from the FUSE spectrum that the white dwarf is rotating with a projected rotational velocity V sin{i} = 600 km/s. Our temperature results provide an additional data point in the distribution of Twd versus orbital period above the CV period gap where few Twds are available.

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P. Godon, L. Seward, E. M. Sion, P. Szkody. 2006-02-06. A Far Ultraviolet Study of the Hot White Dwarf in the Dwarf Nova WW Ceti. https://doi.org/10.1086/501523

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