High-speed photometry of the eclipsing polar UZ Fornacis

Abstract

We present 33 new mid-eclipse times spanning approximately eight years of the eclipsing polar UZ Fornacis. We have used our new observations to test the two-planet model previously proposed to explain the variations in its eclipse times measured over the past $\sim$35 years. We find that the proposed model does indeed follow the general trend of the new eclipse times, however, there are significant departures. In order to accommodate the new eclipse times, the two-planet model requires that one or both of the planets require highly eccentric orbits, that is, $e\ge$ 0.4. Such multiple planet orbits are considered to be unstable. Whilst our new observations are consistent with two cyclic variations as previously predicted, significant residuals remain. We conclude that either additional cyclic terms, possibly associated with more planets, or other mechanisms, such as the Applegate mechanism are contributing to the eclipse time variations. Further long-term monitoring is required.

arXiv comment11 pages, 5 figures, Accepted for publication in A&A

References in corpus (24)

• Achieving better than 1 minute accuracy in the Heliocentric and Barycentric Julian Dates
• The Evolution of Cataclysmic Variables as Revealed by their Donor Stars
• Two planets orbiting the recently formed post-common envelope binary NN Serpentis
• Cataclysmic Variables: An Empirical Angular Momentum Loss Prescription From Open Cluster Data
• Detection of a period decrease in NN Ser with ULTRACAM: evidence for strong magnetic braking or an unseen companion?
• The planets around NN Ser: still there
• Detection of a planetary system orbiting the eclipsing polar HU Aqr
• A dynamical analysis of the proposed HU Aquarii planetary system
• The giant planet orbiting the cataclysmic binary DP Leonis
• Possible detection of two giant extrasolar planets orbiting the eclipsing polar UZ Fornacis
• Eclipsing time variations in close binary systems: Planetary hypothesis vs. Applegate mechanism
• Revisiting the proposed planetary system orbiting the eclipsing polar HU Aquarii
• The HU Aqr planetary system hypothesis revisited
• Long-term eclipse timing of white dwarf binaries: an observational hint of a magnetic mechanism at work
• The orbital period analyses for two cataclysmic variables: UZ Fornacis and V348 Puppis inside Period Gap
• High-Speed Energy-Resolved STJ Photometry of the Eclipsing Binary UZ For
• Polarized QPOs from the INTEGRAL polar IGRJ14536-5522 (=Swift J1453.4-5524)
• The quest for companions to post-common envelope binaries IV: The 2:1 mean-motion resonance of the planets orbiting NN Serpentis
• A Detailed Investigation of the Proposed NN Serpentis Planetary System
• New Light-Travel Time Models and Orbital Stability Study of the Proposed Planetary System HU Aquarii
• The Detection of Dust around NN Ser
• The quest for stable circumbinary companions to post-common envelope sdB eclipsing binaries Does the observational evidence support their existence?
• A burst from the direction of UZ Fornacis with XMM-Newton
• Analysis of astronomical data from optical superconducting tunnel junctions

Cited by in corpus (1)

• A spectroscopic, photometric, polarimetric and radio study of the eclipsing polar UZ Fornacis: the first simultaneous SALT and MeerKAT observations