White Dwarfs and Boundary Layer Structure in Cataclysmic Binaries

Multi-wavelength, multi-component synthetic spectral models of the FUV spectra of cataclysmic variables coupled with evolutionary simulations are yielding deepened insights into the physical structure of CV boundary layers, angular momentum transfer and long term heating during mass accretion onto their white dwarf primaries. By combining spectra from HST, FUSE, IUE, Chandra and XMM, the resulting properties of the underlying accreting white dwarfs form an emerging picture of how long term mass transfer affects their temperatures, rotational velocities, chemical abundances and evolution. We present a summary of the properties of the white dwarf components in long period dwarf novae. Also included is a final summary of WZ Sge three years after its ten years-early super-outburst and the first direct spectroscopic detection of an accreting white dwarf in an AM CVn helium cataclysmic.