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arXiv · 2607.08727

Cataclysmic Variables Photometric Periods from TESS

S. O. Kepler·Alejandra Daniela Romero·Larissa Luciano Amorim·Marcos Perez Diaz
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Abstract

We present a sample of coherent and stable photometric period determinations for cataclysmic variables, based on TESS photometry through sector 102. We analyzed a total of 1554 cataclysmic variable stars and detected periodic variations in 1362 objects, including 286 eclipsing or ellipsoidal-variation systems, 63 polars, and 135 intermediate polars. In particular, we present the first determination of the optical variability period for 564 cataclysmic variables. Due to the 21x21" pixel size of TESS, we tested whether the variability was coming from the cataclysmic variable and not from a nearby star. For the intermediate polars, we detected spin periods in addition to orbital periods for 83 systems. We detect a clear period gap between ~2 and ~3 h in the eclipsing sample, consistent with previous work. The gap remains for the complete sample of photometric variability periods. There is no apparent gap in the orbital period distribution for intermediate polars. Finally, the median of the photometric period distribution of our complete sample of cataclysmic variables is 3.681 h. Comparing this to the distribution of rotation periods for likely single white dwarfs, we find a similar range, with a median photometric period of 6.803~h.

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S. O. Kepler, Alejandra Daniela Romero, Larissa Luciano Amorim, Marcos Perez Diaz. 2026-09-08. Cataclysmic Variables Photometric Periods from TESS. https://arxiv.org/abs/2607.08727

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