Accretion-disc precession in UX Ursae Majoris

Abstract

We report the results of a long campaign of time-series photometry on the nova-like variable UX Ursae Majoris during 2015. It spanned 150 nights, with ~1800 hours of coverage on 121 separate nights. The star was in its normal `high state' near magnitude V=13, with slow waves in the light curve and eclipses every 4.72 hours. Remarkably, the star also showed a nearly sinusoidal signal with a full amplitude of 0.44 mag and a period of 3.680 +/- 0.007 d. We interpret this as the signature of a retrograde precession (wobble) of the accretion disc. The same period is manifest as a +/-33 s wobble in the timings of mid-eclipse, indicating that the disc's centre of light moves with this period. The star also showed strong `negative superhumps' at frequencies w_orb+N and 2w_orb+N, where w_orb and N are respectively the orbital and precession frequencies. It is possible that these powerful signals have been present, unsuspected, throughout the more than 60 years of previous photometric studies.

9 pages, 10 figures, accepted by MNRAS

References in corpus (11)

• The 2001 Superoutburst of WZ Sagittae
• SW Sextantis stars: the dominant population of CVs with orbital periods between 3-4 hours
• PX Andromedae: Superhumps and variable eclipse depth
• HST/FOS Eclipse Observations of the Nova-like Cataclysmic Variable UX Ursae Majoris
• Orbital, Superhump, and Superorbital Periods in the Cataclysmic Variables AQ Mensae and IM Eridani
• Earth, Moon, Sun, and CV Accretion Disks
• Dark spot, Spiral waves and the SW Sex behaviour: it is all about UX Ursae Majoris
• The SW Sex enigma
• The Emergence of Negative Superhumps in Cataclysmic Variables: Smoothed Particle Hydrodynamics Simulations
• Recovery of 29-s Oscillations in HST/FOS Eclipse Observations of the Cataclysmic Variable UX Ursae Majoris
• Modeling UX Ursae Majoris: An abundance of challenges

Cited by in corpus (14)

• A comparative study of the strength of flickering in cataclysmic variables
• TESS light curves of cataclysmic variables -- II: Superhumps in old novae and novalike variables
• IGR J19552+0044: A new asynchronous short period polar: "Filling the gap between intermediate and ordinary polars"
• Discovery of a new classical nova shell around a nova-like cataclysmic variable
• New evidence for the precession of tilted disk in SDSS J081256.85+191157.8
• Tilted discs in six poorly studied cataclysmic variables
• Orbital Period Increase in ES Ceti
• Orbital Period Changes in WZ Sagittae
• A New Window for Studying Intermediate Polars and Tilted Accretion Disk Precession
• Tilted Disk Precession and Negative Superhumps in HS 2325+8205: A Multi-Window Analysis
• Miscellaneous photometric variations in cataclysmic variables: V455 And, SS Cyg, AQ Men, LQ Peg, RW Tri and UX UMa
• Long-term Periodicities of Cataclysmic Variables with Synoptic Surveys
• NSV 1907 - A new eclipsing, nova-like cataclysmic variable
• Extensive Photometry of V1838 Aql during the 2013 Superoutburst