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OY Car During Normal Outburst: Balmer Emission From The Red Star And The Gas Stream

We present observations of OY Car, obtained with the Anglo-Australian Telescope, during a normal outburst in August 1991. Two sinusoidal components are resolved in the H$β$ trailed spectra and we determine the location of the narrow component to be on the secondary star with a maximum contributed flux of ~2.5 per cent to the total flux. Imaging of the line distribution reveals that the other emission component is associated with the gas stream. This follows a velocity close to the ballistic one from the red star to a distance of ~0.5 R$_{L_{1}}$ from the white dwarf. This emission penetrates the accretion disc (from 0.5--0.1 R$_{L_{1}}$), with a velocity now closer (but lower) to the keplerian velocities along the path of the gas stream. We finally discuss the implications of having observed simultaneously line emission from the gas stream and the red star during outburst.