| Title: |
An eclipsing 8.56 minutes orbital period mass-transferring binary |
| Authors: |
Chickles, E.T.; Chakraborty, J.; Burdge, K.B.; Dhillon, V.S.; Draghis, P.; El-Badry, K.; Green, M.J.; Householder, A.; Hughes, S.; Layden, C.; Littlefair, S.P.; Munday, J.; Pelisoli, I.; Redden, M.S.; Tonry, J.; van Roestel, J.; Angile, F.E.; Brown, A.J.; Segura, N.C.; Dinsmore, J.; Dyer, M.; Furesz, G.; Gabutti, M.; Garbutt, J.; García-Mejía, J.; Jarvis, D.; Kennedy, M.R.; Kerry, P.; McCormac, J.; Mo, G.; Osip, D.; Parsons, S.; Pike, E.; Piotrowski, J.J.; Romani, R.W.; Sahman, D.; Simcoe, R. |
| Publisher Information: |
American Astronomical Society |
| Publication Year: |
2026 |
| Collection: |
White Rose Research Online (Universities of Leeds, Sheffield & York) |
| Description: |
We report the discovery of ATLAS J101342.5−451656.8 (hereafter ATLAS J1013−4516), an 8.56 minute orbital-period mass-transferring AM Canum Venaticorum (AM CVn) binary with a mean Gaia magnitude of G = 19.51, identified via periodic variability in light curves from the Asteroid Terrestrial-impact Last Alert System (ATLAS) of Gaia white dwarf candidates. Follow-up with the Large Lenslet Array Magellan Spectrograph shows a helium-dominated accretion disk, and high-speed ULTRACAM photometry reveals pronounced primary and secondary eclipses. We construct a decade-long timing baseline leveraging light curves from the ATLAS and Gaia surveys, as well as the high-speed imagers ULTRACAM on the New Energy Telescope and proto-Lightspeed on the Magellan Clay telescope. From this timing baseline, we measure an orbital period derivative of Ṗ=−1.60±0.07×10−12 s s−1. Interpreted in the context of stable mass transfer, the magnitude and sign of Ṗ indicate that the orbital evolution is governed by the interplay between gravitational-wave-driven angular-momentum losses and mass transfer, directly probing the donor’s structural response to mass loss. We constrain the accretor and donor mass based on stable mass-transfer arguments assuming angular-momentum loss dominated by gravitational-wave emission, allowing us to infer the characteristic gravitational wave strain of the binary for future space-based GW observatories such as the Laser Interferometer Space Antenna (LISA). We predict a characteristic strain corresponding to a 4 yr LISA signal-to-noise ratio ≳10, establishing ATLAS J1013−4516 as a strong prospective LISA source that will probe long-term orbital evolution in the mass-transferring regime. |
| Document Type: |
article in journal/newspaper |
| File Description: |
text |
| Language: |
English |
| ISSN: |
0004-637X |
| Relation: |
https://eprints.whiterose.ac.uk/id/eprint/239794/1/Chickles_2026_ApJ_1000_237.pdf; Chickles, E.T., Chakraborty, J., Burdge, K.B. et al. (34 more authors) (2026) An eclipsing 8.56 minutes orbital period mass-transferring binary. The Astrophysical Journal, 1000 (2). p. 237. ISSN: 0004-637X |
| Availability: |
https://eprints.whiterose.ac.uk/id/eprint/239794/; https://eprints.whiterose.ac.uk/id/eprint/239794/1/Chickles_2026_ApJ_1000_237.pdf |
| Rights: |
cc_by_4 |
| Accession Number: |
edsbas.4BBEBCCD |
| Database: |
BASE |