Resynchronization of the Asynchronous Polar CD Ind

Abstract

CD Ind is one of only four confirmed asynchronous polars (APs). APs are strongly magnetic cataclysmic variables of the AM Herculis subclass with the characteristic that their white dwarfs rotate a few per cent out of synchronism with their binary orbit. Theory suggests that nova eruptions disrupt previously synchronized states. Following the eruption, the system is expected to rapidly resynchronize over a timescale of centuries. The other three asynchronous polars - V1432 Aql, BY Cam and V1500 Cyg - have resynchronization time estimates ranging from 100 to more than 3500 years, with all but one being less than 1200 years. We report on the analysis of over 46000 observations of CD Ind taken between 2007 and 2016, combined with previous observations from 1996, and estimate a CD Ind resynchronization time of 6400 +/- 800 years. We also estimate an orbital period of 110.820(1) minutes and a current (2016.4) white dwarf spin period of 109.6564(1) minutes.

13 pages, 6 figures, to be published in PASP

References in corpus (5)

• Astropy: A Community Python Package for Astronomy
• Magnetic White Dwarfs
• RX J2115-5840: confirmation of a new near-synchronous polar
• Non-Detection of Nova Shells Around Asynchronous Polars
• The near-synchronous polar V1432 Aql (RX J1940.1-1025): Accretion geometry and synchronization time scale

Cited by in corpus (9)

• Galactic Model Parameters and Space Density of Cataclysmic Variables in Gaia Era: New Constraints to Population Models
• Multi-band study of RX J0838-2827 and XMM J083850.4-282759: a new asynchronous magnetic cataclysmic variable and a candidate transitional millisecond pulsar
• Fast-Cadence TESS Photometry and Doppler Tomography of the Asynchronous Polar CD Ind: A Revised Accretion Geometry from Newly Proposed Spin and Orbital Periods
• TESS observations of the asynchronous polar CD Ind: mapping the changing accretion geometry
• Kepler K2 and TESS observations of two magnetic cataclysmic variables: The new asynchronous polar SDSS J084617.11+245344.1 and Paloma
• Spot Model for Identifications of Periods in Asynchronous Polars
• Swift J0503.7-2819: A Short-Period Asynchronous Polar or Stream-Fed Intermediate Polar
• A broadband X-ray study of the asynchronous polar: CD Ind
• A systematic search for orbital periods of polars with TESS. Methods, detection limits, and results