A SPECTROSCOPIC STUDY OF THE DWARF NOVA KT-PERSEI

We present H alpha radial velocities of KT Per taken during quiescence (1989 November) and outburst (1990 February). Both data sets indicate an orbital period near 3.90 hr, confirming the result of Ratering et al. (A&A, 268, 684, 1993). We could not refine the period unambiguousl y; combining our velocities with those of Ratering et al. (1993) shows that the period is most likely near 0.1627 d, but a period near 0.161 8 d is just possible if one forces coherence between the the outburst and quiescent velocities. Another possibility is that the phase of the emission-line velocities in outburst lags that of the quiescent veloc ities by similar to 1/4 cycle. We detect the secondary star, estimate its spectral type as M3, and from this derive a distance of 245+/-100 pc. After subtracting the secondary contribution, we find that the nea r-infrared continuum steepens considerably during outburst. KT Per app ears to be a normal dwarf nova, although its period is among the short er dwarf-nova periods longward of the 2- to 3-hr gap. An absorption fe ature near lambda 6280, which had been noted by Ratering et al., is id entified as a telluric O-2 band.