A spectroscopic study of the deeply eclipsing dwarf nova IP Peg.

Spectrophotometry of the dwarf nova IP Peg during quiescence is presented. The spectra have broad, double-peaked emission lines on a blue continuum, characteristic of high-inclination dwarf novae. The emission lines are 96 percent eclipsed and the orbital hump, which is strong in the continuum, is much weaker in the lines. A method for analysis of radial velocities of emission lines is introduced which corrects for bias caused by disk asymmetries, and the geometrical and physical parameters of IP Peg are determined. The analysis of the eclipse shows good agreement with an accretion disk in Keplerian rotation around the white dwarf. The width of the white dwarf eclipse was measured from the eclipse of the high-velocity emission, and the time of mideclipse was determined. The radius of the accretion disk during the observations is roughly half the inner Lagrangian point distance, and just larger than the radius of total eclipse.