CCD Height Effects on Rubin PSFs

Abstract

Modeling the point-spread function (PSF) precisely is essential for many– if not all– science cases with the Rubin Observatory. In this work, we inspect a PSF residual pattern present in both Rubin’s ComCam and LSSTCam observations. We show that it is likely due to effects from CCD non-flatness, and elaborate on the mechanism by which height offsets could influence the PSF. Finally, we demonstrate that incorporating height information into PSF modeling greatly reduces the observed residual.