An eclipsing 8.56 minute orbital period mass-transferring binary
Emma T. Chickles (Massachusetts Institute of Technology, Cambridge, USA), Joheen Chakraborty (Massachusetts Institute of Technology, Cambridge, USA), Kevin B. Burdge (Massachusetts Institute of Technology, Cambridge, USA), Vik S. Dhillon (University of Sheffield, Sheffield, UK, Instituto de Astrofisica de Canarias, La Laguna, Spain), Paul Draghis (Massachusetts Institute of Technology, Cambridge, USA), Kareem El-Badry (California Institute of Technology, Pasadena, USA), Matthew J. Green (Max Planck Institute for Astronomy, Heidelberg, Germany), Aaron Householder (Massachusetts Institute of Technology, Cambridge, USA), Sarah Hughes (Massachusetts Institute of Technology, Cambridge, USA), Christopher Layden (Massachusetts Institute of Technology, Cambridge, USA), Stuart P. Littlefair (University of Sheffield, Sheffield, UK), James Munday (University of Warwick, Coventry, UK), Ingrid Pelisoli (University of Warwick, Coventry, UK), Maya S. Redden (Stanford University, Stanford, USA), John Tonry (University of Hawaii, Honolulu, USA), Jan van Roestel (Institute of Science and Technology Austria, Klosterneuburg, Austria, University of Amsterdam, Amsterdam, The Netherlands), F. Elio Angile (Massachusetts Institute of Technology, Cambridge, USA), Alex J. Brown (University of Hamburg, Hamburg, Germany), Noel Castro (University of Warwick, Coventry, UK), Jack Dinsmore (Stanford University, Stanford, USA), Martin Dyer (University of Sheffield, Sheffield, UK, Research Software Engineering, University of Sheffield, Sheffield, UK), Gabor Furesz (Massachusetts Institute of Technology, Cambridge, USA), Michelle Gabutti (Massachusetts Institute of Technology, Cambridge, USA), James Garbutt (University of Sheffield, Sheffield, UK), Daniel Jarvis (University of Sheffield, Sheffield, UK), Mark R. Kennedy (University College Cork, Cork, Ireland), Paul Kerry (University of Sheffield, Sheffield, UK), James McCormac (University of Warwick, Coventry, UK), Geoffrey Mo (California Institute of Technology, Pasadena, USA, Carnegie Observatories, Pasadena, USA), Dave Osip (Las Campanas Observatory, La Serena, Chile), Steven Parsons (University of Sheffield, Sheffield, UK), Eleanor Pike (University of Sheffield, Sheffield, UK), Jack Piotrowski (Carnegie Observatories, Pasadena, USA), Roger W. Romani (Stanford University, Stanford, USA), David Sahman (University of Sheffield, Sheffield, UK), Rob Simcoe (Massachusetts Institute of Technology, Cambridge, USA)
arXiv:2601.07925v2 Announce Type: replace
Abstract: We report the discovery of ATLAS J101342.5-451646.8 (hereafter ATLAS J1013-4516), an eclipsing, mass-transferring AM Canum Venaticorum binary with an 8.56-minute orbital period, identified via periodic variability in light curves from the Asteroid Terrestrial-impact Last Alert System survey of Gaia white dwarf candidates. Follow-up spectroscopy with the Large Lenslet Array Magellan Spectrograph reveals a helium-dominated accretion disk, while high-speed photometry with ULTRACAM shows pronounced primary and secondary eclipses. We construct a decade-long timing baseline using data from ATLAS, Gaia, ULTRACAM on the New Technology Telescope, and the proto-Lightspeed instrument on the Magellan Clay telescope. From this baseline, we measure an orbital period derivative of dP/dt = -1.60 +/- 0.07 x 10^-12 seconds per second. Interpreted in the context of stable mass transfer, the magnitude and sign of the period derivative indicate that the orbital evolution is governed by the interplay between gravitational-wave-driven angular momentum losses and mass transfer, directly probing the donor star’s structural response to mass loss. Assuming angular momentum loss dominated by gravitational wave emission, we constrain the component masses and infer the characteristic gravitational wave strain of the system for future space-based observatories such as the Laser Interferometer Space Antenna. We predict a characteristic strain corresponding to a four-year signal-to-noise ratio greater than approximately 20, establishing ATLAS J1013-4516 as a strong prospective source for probing long-term orbital evolution in the mass-transferring regime.arXiv:2601.07925v2 Announce Type: replace
Abstract: We report the discovery of ATLAS J101342.5-451646.8 (hereafter ATLAS J1013-4516), an eclipsing, mass-transferring AM Canum Venaticorum binary with an 8.56-minute orbital period, identified via periodic variability in light curves from the Asteroid Terrestrial-impact Last Alert System survey of Gaia white dwarf candidates. Follow-up spectroscopy with the Large Lenslet Array Magellan Spectrograph reveals a helium-dominated accretion disk, while high-speed photometry with ULTRACAM shows pronounced primary and secondary eclipses. We construct a decade-long timing baseline using data from ATLAS, Gaia, ULTRACAM on the New Technology Telescope, and the proto-Lightspeed instrument on the Magellan Clay telescope. From this baseline, we measure an orbital period derivative of dP/dt = -1.60 +/- 0.07 x 10^-12 seconds per second. Interpreted in the context of stable mass transfer, the magnitude and sign of the period derivative indicate that the orbital evolution is governed by the interplay between gravitational-wave-driven angular momentum losses and mass transfer, directly probing the donor star’s structural response to mass loss. Assuming angular momentum loss dominated by gravitational wave emission, we constrain the component masses and infer the characteristic gravitational wave strain of the system for future space-based observatories such as the Laser Interferometer Space Antenna. We predict a characteristic strain corresponding to a four-year signal-to-noise ratio greater than approximately 20, establishing ATLAS J1013-4516 as a strong prospective source for probing long-term orbital evolution in the mass-transferring regime.