Characteristics of the Permanent Superhumps in V533 Herculis

Abstract

We analyze two sectors of TESS photometry of the nova-like cataclysmic variable star V533 Her. We detect a periodicity consistent with the binary orbital period and estimate a revised value of 3.53709(2) hr. We also detect a strong signal near a period of 3.8 h that we associate with positive superhumps. The superhump frequency varies over the TESS observations with the fractional difference between the superhump and orbital periods, $\epsilon$, ranging between $0.055\le \epsilon \le 0.080$. The superhump amplitude is correlated with its frequency such that the amplitude increases as $\epsilon$ decreases. Positive superhumps result from an instability that generates an eccentric accretion disk and $\epsilon$ is a measure of the disk precession rate in the binary rest frame. The observed correlation implies that as the disk precession rate slows, the disk eccentricity increases.

arXiv comment4 pages, 1 figure, accepted for publication in the RNAAS

References in corpus (5)

• Astropy: A Community Python Package for Astronomy
• The Evolution of Cataclysmic Variables as Revealed by their Donor Stars
• Superhumps in Cataclysmic Binaries. XXV. q_crit, epsilon(q), and Mass-Radius
• A Comprehensive K2 and Ground-Based Study of CRTS J035905.9+175034, an Eclipsing SU UMa System with a Large Mass Ratio
• Far Ultraviolet Spectroscopy of Old Novae II: RR Pic, V533 Her and DI Lac

Cited by in corpus (1)

• TESS light curves of cataclysmic variables I -- Unknown periods in long-known stars