An Atlas of the Lyman-$\alpha$ Region for a Grid of Dwarf Nova Accretion Disk Models
Session 63 -- Intrinsic and Cataclysmic Variables
Display presentation, Thursday, 9:20-4:00, Heller Lounge Room

## [63.12] An Atlas of the Lyman-$\alpha$ Region for a Grid of Dwarf Nova Accretion Disk Models

R.A. Wade (Penn State), I. Hubeny (GSFC/USRA), R.S. Polidan (NASA/GSFC)

We use the accretion disk modeling code TLUSDISK and spectrum synthesis tools to compute a grid of spectra between 900 and 1500 \AA\ for accretion disks of cataclysmic variables in quiescence. The disk models and spectra are calculated in LTE. A contribution from the white dwarf is included, for a variety of white dwarf effective temperatures. The occultation of part of the inner disk by the white dwarf is also taken into account. The contribution of a boundary layer, assumed to be optically thin and emitting primarily at x-ray temperatures, is neglected.

The mass and radius of the accreting white dwarf are varied. The mass accretion rate, assumed to be steady, is chosen to reproduce the estimated luminosities of quiescent dwarf novae. The emergent spectra are presented for a variety of inclination angles, to show the effect of Doppler broadening at a resolution similar to that of the Hopkins Ultraviolet Telescope and somewhat better than that of low-dispersion IUE spectra. Comparisons of the Lyman-$\alpha$ region with some IUE spectra of dwarf novae in quiescence are attempted.

Supported by NASA grant NAG 5-2125.