An extensive photometric study of the recently discovered intermediate polar V515 And (XSS J00564+4548)

TL;DR

This study presents detailed photometric observations of the intermediate polar V515 And, revealing its white dwarf spin and orbital periods, and analyzing pulse profile stability over 33 nights.

Contribution

First extensive photometric analysis of V515 And, identifying its spin and orbital periods and pulse profile behaviors over multiple nights.

Findings

Detected two oscillations at 465.48 s and 488.62 s

Identified the orbital period as 2.73 hours

V515 And is among the fastest spinning intermediate polars

Abstract

We report results of photometry of the intermediate polar V515 And. The observations were obtained over 33 nights in 2008 and 2009. The total duration of the observations was 233 h. We clearly detected two oscillations with periods of 465.48493\pm0.00007$ and 488.61822\pm0.00009 s, which may be the white dwarf spin period and the orbital sideband. The semi-amplitudes of the oscillations are 25 and 20 mmag, accordingly. The oscillation with a period of 465.48493 s has a stable smooth asymmetric pulse profile whereas the pulse profile of the oscillation with a period of 488.61822 s reveals significant changes from a quasi-sinusoidal shape to a shape somewhat resembling a light-curve of an eclipsing binary. Two detected oscillations imply an orbital period of 2.73 h. V515 And is one of the most rapidly spinning intermediate polars with orbital periods less than 3 h and may be not in spin equilibrium. This can be proved by future observations. For this purpose we obtained oscillation ephemerises with a formal shelf life of about 100 yr. (a 1 sigma confidence level).