Large-Amplitude 2.65-d Oscillation in the VY Scl-Type star V425 Cas

Abstract

From long-term photometry of a VY Scl-type star, V425 Cas, between 1998 and 2000, we discovered a short-term, large-amplitude (up to 1.5 mag) variations. The variation was well represented by a single period of 2.65 d. The large amplitude and the profile of the folded light curve suggest that the dwarf nova-type disk instability is responsible for this variation. The shortness of the period is unprecedented in hydrogen-rich cataclysmic variables. Given the recent emerging evidence that the irradiation from white dwarfs in VY Scl-type systems affect their light behavior, we propose a possibility that this unique variation in V425 Cas can be explained by the combination of the dwarf nova-type disk instability and irradiation. Similar short-period "outbursts" have been known in X-ray transients (V518 Per), and helium cataclysmic variables (CR Boo and V803 Cen). We discuss the possibility that these phenomena have a common origin to the unique variation in V425 Cas.

6 pages, 5 figures, accepted for publication in Publ. Astron. Soc. Japan

Cited by in corpus (7)

• Variable Star Network: World Center for Transient Object Astronomy and Variable Stars
• TESS light curves of cataclysmic variables -- III -- More superhump systems among old novae and novalike variables
• Photometric Study of KR Aurigae during the High State in 2001
• V803 Centauri: Helium Dwarf Nova Mimicking a WZ Sge-Type Superoutburst
• The photometric and spectral investigation of CI Camelopardalis, an X-ray transient and B[e] star
• Detection of Short Fading Episodes in Two Dwarf Novae from VSNET Observations
• The Extended Deep Minimum and the Subsequent Brightening of RX And in 1996-1997