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Time-resolved observations of the short period CV SDSS J123813.73-033933

S. V. Zharikov·G. H. Tovmassian·V. Neustroev·R. Michel·R. Napiwotzki
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Abstract

We present simultaneous spectral and photometric observations of SDSS J123813.73-033933.0. From Ha radial velocity measurements we determined the orbital period of the system to be 0.05592+/-0.00002 days (80.53 min). The spectrum shows double Balmer emission lines flanked by strong, broad absorption, indicating a dominant contribution from the white dwarf. The photometric light curve shows complex variability. The system undergoes cyclic brightening up to 0.4 mag which are semi-periodical on short time scales with periods of the order of 7-12 hours. We also detect 40.25 min variability (~0.15 mag) in the light curve, that corresponds to half the orbital period. Its amplitude increases with the cyclic brightening of the system.

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S. V. Zharikov, G. H. Tovmassian, V. Neustroev, R. Michel, R. Napiwotzki. 2004-09-27. Time-resolved observations of the short period CV SDSS J123813.73-033933. https://arxiv.org/abs/astro-ph/0409647

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