Kepler Extra-Galactic Survey ("KEGS")

The light curves from K2 contain larger systematics than the original Kepler mission, due to the reduction in pointing precision as a result of having to rely on only two reaction wheels. The KEGS project creates detrended light curves for extragalactic targets observed in K2. The team determines optimal apertures that take into account background light and confusing neighboring sources while also maximizing light of the galaxies. The team constructs their own cotrending basis vectors (CBVs) using the galaxies on each channel via a PCA analysis, solving for CBV coefficients alongside the sawtooth pattern coefficients introduced by the pointing drift. Supernovae are analyzed in a similar fashion, but the light curves before and after the events are used to solve for the CBV coefficients.<br> The team have released their extracted light curves and diagnostic plots for each target. Five versions of the light curves are available for each target, using a different number of CBVs. Diagnostic plots are provided by the KEGS team that show each target on a given Kepler module as well. These plots can be used to check for similar variability between targets, which could be indicative of false positive variability caused by uncorrected systematics. The apertures used for each target are also available within the FITS files.