Doppler Tomography of the Dwarf Nova IY UMa During Quiescence

Abstract

Quiescent Doppler tomography of the newly discovered deeply-eclipsing SU UMa system IY UMa reveals properties of the region where the accretion stream from the donor impacts the edge of the disc. A very strong bright spot is produced and the Keplerian disc emission in the impact region is disrupted or obscured. The differing properties of Hα, Hβ and He I emission will allow physical parameters of the converging flow region to be studied