A New Variable in the Field of WD1145+017

Abstract

Revisit of the CCD archive obtained during long-time monitoring of the white dwarf WD1145+015 at Tien-Shan Observatory revealed a new variable star, identified as Gaia DR2 3796400796427214848. It was inferred that this star is of spectral type G7V-G8V. The amount of photometric data allows performing detailed analysis of this target, revealing its rotational-modulation variability. The period of variation is 6.33 h which makes this star an ultra-fast rotator. The stability of variability might be due to ``magnetic saturation" of the angular momentum loss. Yet another possible interpretation of the brightness variation is an elliptical variable binary system.