A Phenomenon Resembling Early Superhumps in a New SU UMa-type Dwarf Nova with a 2 hr Orbital Period

A Phenomenon Resembling Early Superhumps in a New SU UMa-type Dwarf Nova with a 2 hr Orbital Period

Blog Article

We investigate K2BS5, an optical transient that we identified in Campaign 13 of the Kepler/K2 archives by the K2 Background Survey, and classify it as a new SU UMa-type dwarf nova.Using the Winter Sports - Soft Goods - Baselayer light curve generated from Keplers long-cadence observation mode, we analyze the dwarf nova during quiescence and superoutburst.Following 20 days of quiescence at the start of the observation, the system entered a superoutburst lasting 12 days, after which it experienced at least one rebrightening.

K2BS5 clearly meets the criteria for an SU UMa star, but Saddle Riggings » Backriggings at the peak of the superoutburst, it also shows double-wave oscillations consistent with the spectroscopic orbital period, a phenomenon that closely resembles early superhumps in WZ Sge stars.While we do not classify K2BS5 as a WZ Sge system, we discuss how this phenomenon could complicate efforts to use the suspected detection of early superhumps to distinguish SU UMa-type dwarf novae from the recently recognized class of long-orbital-period WZ Sge systems.