Exposed white dwarfs in dwarf novae

Abstract

Hubble Space Telescope far ultraviolet spectroscopic observations of cataclysmic variable white dwarfs, exposed during dwarf nova quiescence, have yielded a number of new insights on accretional heating, photospheric abundances of the accreted atmosphere and rotational velocities of the underlying degenerates. Recent results of synthetic spectral analyses of HST spectra (and, in some cases, IUE spectra) are highlighted together with comparisons between time-dependent theoretical simulations of the heating effect of the dwarf nova accretion event on the underlying degenerate and actual spectroscopic observations of white dwarf surface cooling.