Two Candidate KH 15D–like Systems from the Zwicky Transient Facility

Abstract

KH 15D contains a circumbinary disk that is tilted relative to the orbital plane of the central binary. The precession of the disk and the orbital motion of the binary together produce rich phenomena in the photometric light curve. In this work, we present the discovery and preliminary analysis of two objects that resemble the key features of KH 15D from the Zwicky Transient Facility. These new objects, Bernhard-1 and Bernhard-2, show large-amplitude ( >1.5 mag), long-duration (more than tens of days), and periodic dimming events. A one-sided screen model is developed to model the photometric behavior of these objects, the physical interpretation of which is a tilted, warped circumbinary disk occulting the inner binary. Changes in the object light curves suggest potential precession periods over timescales longer than 10 yr. Additional photometric and spectroscopic observations are encouraged to better understand the nature of these interesting systems.