Nova Sagittarii 1998 (V4633 Sgr) - a permanent superhump system or an asynchronous polar?

Y. Lipkin; E. M. Leibowitz; A. Retter; O. Shemmer

doi:10.1046/j.1365-8711.2001.04962.x

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Nova Sagittarii 1998 (V4633 Sgr) - a permanent superhump system or an asynchronous polar?

Y. Lipkin·E. M. Leibowitz·A. Retter·O. Shemmer

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Abstract

We report the results of observations of V4633 Sgr (Nova Sagittarii 1998) during 1998-2000. Two photometric periodicities were present in the light curve during the three years of observations: a stable one at P=3.014 h, 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 P=5.06 d, corresponding to the beat between the two periods was probably present in 1999. Our results suggest that a process of mass transfer took place in the binary system since no later than two and a half months after the nova eruption. We derive an interstellar reddening of E(B-V)~0.21 from our spectroscopic measurements and published photometric data, and estimate a distance of d~9 kpc to this nova.

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Y. Lipkin, E. M. Leibowitz, A. Retter, O. Shemmer. 2001-09-10. Nova Sagittarii 1998 (V4633 Sgr) - a permanent superhump system or an asynchronous polar?. https://doi.org/10.1046/j.1365-8711.2001.04962.x

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