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Paper: O - C Analysis of the Intermediate Polar BG CMi
Volume: 335, The Light-Time Effect in Astrophysics: Causes and Cures of the O - C diagram
Page: 355
Authors: Andronov, I.L.; Kim, Y.G.; Shin, J.-H.; Jeon, Y.B.
Abstract: Based on 1066 CCD observations obtained in 2002–2004 at the 1.8-m telescope of the Korean Astronomy observatory, the 15-min variability of BG CMi is analyzed. Moments and brightness at 58 maxima and 63 minima are tabulated. The maxima correspond better to the cubic polynomial ephemeris of Garlick et al. (1994) then to the more recent quadratic model of Pych et al. (1996). The mean phase of maxima, according to the cubic ephemeris, is only 0.109 ± 0.18; whereas the maxima for seasons 2002 and 2004 are in antiphase, if computed using the quadratic ephemeris. A cycle miscount is possible, producing more complicated (e.g. cyclic) variations of the period. An apparent acceleration of the spin-up may be the result from changes of the equilibrium period, which are caused by variations of the magnetic field strength and/or orientation.
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