Transit-APP: A Centroid-free Method of Identifying Background Transit False Positives

Abstract We present a centroid-free method to identify which star is the source of a known transit signal from pixel data. This method is based on observed and simulated difference images, and provides a relative probability of a star being the source of the transit compared to other known stars. This method is robust at low S/N compared to common centroid-based methods, and is well suited for space-based transit surveys such as Kepler and TESS.