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arXiv · 2610.40346

Six New Eclipsing AM CVn Binaries from the Zwicky Transient Facility

Aaron Householder·Kevin B. Burdge·Yapeng Zhang·Emma Chickles·Jan van Roestel·Matthew J. Green·Kaley Brauer·Joheen Chakraborty·Jack Dinsmore·Gabor Furesz·Juliana García-Mejía·Matthew J. Graham·Aurora Y. Kesseli·Shrinivas R. Kulkarni·Christopher Layden·Geoffrey Mo·David Osip·Roger W. Romani·Andrew Vanderburg
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Abstract

We present the discovery of six new eclipsing AM CVn binaries, helium-accreting ultracompact systems in which a cool donor eclipses the accreting white dwarf. The systems were found in a GPU-accelerated Box Least Squares (BLS) search of Zwicky Transient Facility (ZTF) photometry and have orbital periods of 39.3 to 59.9 minutes. We obtained spectroscopy with the Low Resolution Imaging Spectrometer (LRIS) on the Keck I telescope for all six systems, and every spectrum shows helium emission with no detectable hydrogen, confirming their AM CVn classification. Our discoveries increase the number of deeply eclipsing AM CVn from 11 to 17 (i.e., systems in which the accreting white dwarf is both the dominant source of optical light and eclipsed by the donor). With high-speed photometric follow-up, these systems will provide the mass ratios, inclinations, and fractional radii of both components. They will also provide new tests of AM CVn formation models and stronger constraints on the long-term evolution of these sources.

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Aaron Householder, Kevin B. Burdge, Yapeng Zhang, Emma Chickles, Jan van Roestel, Matthew J. Green, Kaley Brauer, Joheen Chakraborty, Jack Dinsmore, Gabor Furesz, Juliana García-Mejía, Matthew J. Graham, Aurora Y. Kesseli, Shrinivas R. Kulkarni, Christopher Layden, Geoffrey Mo, David Osip, Roger W. Romani, Andrew Vanderburg. 2026-10-29. Six New Eclipsing AM CVn Binaries from the Zwicky Transient Facility. https://arxiv.org/abs/2610.40346

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