Nova Sagittarii 1998 (V4633 Sgr): a permanent superhump system or an asynchronous polar? |
| |
| Authors: | Y Lipkin EM Leibowitz A Retter O Shemmer |
| |
| Institution: | 1School of Physics and Astronomy, and the Wise Observatory, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv 69978, Israel;2Department of Physics, Keele University, Keele, Staffordshire ST5 5BG;3School of Physics, University of Sydney, 2006, Australia |
| |
| Abstract: | We report the results of observations of V4633 Sgr (Nova Sagittarii 1998) during  . Two photometric periodicities were present in the light curve during the three years of observations: a stable one at  , which is probably the orbital period of the underlying binary system; and a second one of lower coherence, approximately 2.5 per cent longer than the former. The latter periodicity may be a permanent superhump, or, alternatively, the spin period of the white dwarf in a nearly synchronous magnetic system. A third period, at  , corresponding to the beat between the two periods was probably present in 1999. Our results suggest that a process of mass transfer has taken place in the binary system since no later than two-and-a-half months after the nova eruption. We derive an interstellar reddening of  from our spectroscopic measurements and published photometric data, and estimate a distance of  to this nova. |
| |
| Keywords: | accretion accretion discs stars: individual: V4633 Sgr novae cataclysmic variables |
|
|
