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1RXS J232953.9+062814: a New SU UMa Dwarf Nova below the Period Minimum

J. Y. Wei·X. J. Jiang·D. W. Xu·A. Y. Zhou·J. Y. Hu
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Abstract

1RXS J232953.9+062814 was identified as a cataclysmic variable by Wei et al. (1999). Four low-resolution spectra of 1RXS J232953.9+062814 were obtained by using the 2.16-m telescope of the National Astronomical Observatories, in which two of them were at outburst, and the other two were at quiescence. The system is about 16.8 B and 16.5 V at quiescence, and 12.6 B and 12.6 V at outburst. The quiescent spectra were dominated by double-peaked Balmer emissions, which indicates a hydrogen-rich system with a high-inclination accretion disc. MgH and TiO absorption bands appeared in the quiescent spectrum imply a companion with a spectral type of early M dwarf. If we take it as a M0 dwarf, the system is located at a distance of 350 pc with a proper motion velocity 150 km s$^{-1}$. The superhump period of 0.046311 days (Uemura et al. 2001) was confirmed by our V photometry. The short period and the hydrogen-rich nature reveal that this system is another SU Ursae Majoris-type dwarf nova below the period minimum after V485 Centauri. 1RXS J232953.9+062814 is one of the most important systems for studying the evolutionary scenario of cataclysmic variables since it is much brighter than V485 Cen.

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J. Y. Wei, X. J. Jiang, D. W. Xu, A. Y. Zhou, J. Y. Hu. 2001-12-02. 1RXS J232953.9+062814: a New SU UMa Dwarf Nova below the Period Minimum. https://doi.org/10.1088/1009-9271%2F1%2F6%2F483

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