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We present an analysis of 168 oscillating red giants from NASA's $Kepler$mission that exhibit anomalous peaks in their Fourier amplitude spectra. Thesepeaks result from ellipsoidal variations which are indicative of binary starsystems, at frequencies such that the orbit of any stellar companion would bewithin the convective envelope of the red giant. Alternatively, the observedphenomenon may be due to a close binary orbiting a red giant in a triplesystem, or chance alignments of foreground or background binary systemscontaminating the target pixel aperture. We identify 87 stars in the sample aschance alignments using a combination of pixel Fourier analysis and differenceimaging. We find that in the remaining 81 cases the anomalous peaks areindistinguishable from the target star to within 4$''$, suggesting a physicalassociation. We examine a Galaxia model of the $Kepler$ field of view toestimate background star counts and find that it is highly unlikely that alltargets can be explained by chance alignments. From this, we conclude thatthese stars may comprise a population of physically associated systems.

Evidence for compact binary systems around Kepler red giants