Orbital decay in an accreting and eclipsing 13.7 minute orbital period binary with a luminous donor

Abstract

We report the discovery of ZTF J0127+5258, a compact mass-transferring binary with an orbital period of 13.7 minutes. The system contains a white dwarf accretor, which likely originated as a post-common envelope carbon-oxygen (CO) white dwarf, and a warm donor ($T_{\mathrm{eff},\mathrm{donor}}=16,400\pm 1000\mathrm{K}$). The donor probably formed during a common envelope phase between the CO white dwarf and an evolving giant which left behind a helium star or helium white dwarf in a close orbit with the CO white dwarf. We measure gravitational wave-driven orbital inspiral with $\sim 35\sigma$ significance, which yields a joint constraint on the component masses and mass transfer rate. While the accretion disk in the system is dominated by ionized helium emission, the donor exhibits a mixture of hydrogen and helium absorption lines. Phase-resolved spectroscopy yields a donor radial-velocity semi-amplitude of $771\pm 27\mathrm{km}{\mathrm{s}}^{-1}$, and high-speed photometry reveals that the system is eclipsing. We detect a {\it Chandra} X-ray counterpart with $L_X\sim 3\times 10^{31}\mathrm{erg}{\mathrm{s}}^{-1}$. Depending on the mass-transfer rate, the system will likely evolve into either a stably mass-transferring helium CV, merge to become an R Crb star, or explode as a Type Ia supernova in the next million years. We predict that the Laser Space Interferometer Antenna (LISA) will detect the source with a signal-to-noise ratio of $24\pm 6$ after 4 years of observations. The system is the first \emph{LISA}-loud mass-transferring binary with an intrinsically luminous donor, a class of sources that provide the opportunity to leverage the synergy between optical and infrared time domain surveys, X-ray facilities, and gravitational-wave observatories to probe general relativity, accretion physics, and binary evolution.

13 pages, 7 figures, 2 tables, submitted to ApJL

References in corpus (28)

• Modules for Experiments in Stellar Astrophysics (MESA)
• The Zwicky Transient Facility: System Overview, Performance, and First Results
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• The Zwicky Transient Facility: Data Processing, Products, and Archive
• The Zwicky Transient Facility: Science Objectives
• Modules for Experiments in Stellar Astrophysics (MESA): Time-Dependent Convection, Energy Conservation, Automatic Differentiation, and Infrastructure
• The Zwicky Transient Facility: Observing System
• A statistical test for Nested Sampling algorithms
• Fully-Automated Reduction of Longslit Spectroscopy with the Low Resolution Imaging Spectrometer at Keck Observatory
• A new equation of state for dense hydrogen-helium mixtures
• The Initiation and Propagation of Helium Detonations in White Dwarf Envelopes
• Skye: A Differentiable Equation of State
• Every interacting double white dwarf binary may merge
• The Thermal Evolution of the Donors in AM CVn Binaries
• Orbital Decay in a 20 Minute Orbital Period Detached Binary with a Hydrogen Poor Low Mass White Dwarf
• Long-term Photometric Behavior of Outbursting AM CVn Systems
• A new class of Roche lobe-filling hot subdwarf binaries
• Discovery and characterization of five new eclipsing AM CVn systems
• Discovery of a double detonation thermonuclear supernova progenitor
• LEGWORK: A python package for computing the evolution and detectability of stellar-origin gravitational-wave sources with space-based detectors
• Phases of Mass Transfer from Hot Subdwarfs to White Dwarf Companions and Their Photometric Properties
• Mass Transfer and Stellar Evolution of the White Dwarfs in AM CVn Binaries
• Two decades of optical timing of the shortest-period binary star system HM Cancri
• A 62-minute orbital period black widow binary in a wide hierarchical triple
• Evidence that short period AM CVn systems are diverse in outburst behaviour
• A dense $0.1{\mathbf{M}}_{\odot }$ star in a 51-minute orbital period eclipsing binary
• GALEX J194419.33+491257.0: An Unusually Active SU UMa-Type Dwarf Nova with a Very Short Orbital Period in the Kepler Data
• Orbital Period Increase in ES Ceti

Cited by in corpus (7)

• The Lunar Gravitational-wave Antenna: Mission Studies and Science Case
• The BlackGEM telescope array I: Overview
• A Catalogue of Ultracompact Mass-Transferring White Dwarf Binaries
• Astrophysical Parameter Inference on Accreting White Dwarf Binaries using Gravitational Waves
• Precise Parameters for Two LISA Sources
• Classification of IGR J20084+3221 as an Intermediate Polar using X-ray and Optical Observations
• Rapid Orbital Decay in the Ultracompact Double-degenerate Binary eRASSU J060839.5$-$704014