K2 Variable Catalogue: Variable Stars and Eclipsing Binaries in K2 Campaigns 1 and 0

TL;DR

This paper presents a comprehensive catalogue of 8395 variable stars from K2 Campaigns 1 and 0, including eclipsing binaries and periodic variables, with detailed lightcurve analysis and classification.

Contribution

The study introduces a new catalogue of variable stars from K2 data, with algorithmic and human classification, and provides detrended lightcurves and variability parameters.

Findings

Catalogue includes 8395 variable stars and 199 eclipsing binaries.

Lightcurves are extracted, detrended, and classified into various variability types.

Catalogue and lightcurves are publicly available online.

Abstract

We have created a catalogue of variable stars found from a search of the publicly available K2 mission data from Campaigns 1 and 0. This catalogue provides the identifiers of 8395 variable stars, including 199 candidate eclipsing binaries with periods up to 60d and 3871 periodic or quasi-periodic objects, with periods up to 20d for Campaign 1 and 15d for Campaign 0. Lightcurves are extracted and detrended from the available data. These are searched using a combination of algorithmic and human classification, leading to a classifier for each object as an eclipsing binary, sinusoidal periodic, quasi periodic, or aperiodic variable. The source of the variability is not identified, but could arise in the non-eclipsing binary cases from pulsation or stellar activity. Each object is cross-matched against variable star related guest observer proposals to the K2 mission, which specifies the variable type in some cases. The detrended lightcurves are also compared to lightcurves currently publicly available. The resulting catalogue is made available online via the MAST archive at https://archive.stsci.edu/prepds/k2varcat/, and gives the ID, type, period, semi-amplitude and range of the variation seen. We also make available the detrended lightcurves for each object.