OY Car in Outburst: Balmer emission from the red star and the gas stream
Abstract
Description
We present observations of OY Car, obtained with the Anglo-Australian telescope, during a normal outburst in 1991. Two sinusoidal components are resolved in the Hbeta 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_L1 from the white dwarf. Then. its kinematics changes from 0.5-0.2 R_L1 (accretion disc) following velocities now closer to (but lower than) the keplerian velocities along the path of the gas stream. We finally dicsuss the implications of having observed simultaneously line emission from the gas stream and the red star during outburst.
uuencoded compressed postscript, without figures. The preprint is available with figures at http://www.ast.cam.ac.uk/preprint/PrePrint.html
uuencoded compressed postscript, without figures. The preprint is available with figures at http://www.ast.cam.ac.uk/preprint/PrePrint.html