A New Merging Double Degenerate Binary in the Solar Neighborhood

Abstract

Characterizing the local space density of double degenerate binary systems is a complementary approach to broad sky surveys of double degenerates to determine the expected rates of white dwarf binary mergers, in particular those that may evolve into other observable phenomena such as extreme helium stars, Am CVn systems, and supernovae Ia. However, there have been few such systems detected in local space. We report here the discovery that WD 1242$-$105, a nearby bright WD, is a double-line spectroscopic binary consisting of two degenerate DA white dwarfs of similar mass and temperature, despite it previously having been spectroscopically characterized as a single degenerate. Follow-up photometry, spectroscopy, and trigonometric parallax have been obtained in an effort to determine the fundamental parameters of each component of this system. The binary has a mass ratio of 0.7 and a trigonometric parallax of 25.5 mas, placing it at a distance of 39 pc. The system's total mass is 0.95 M${}_{\odot }$ and has an orbital period of 2.85 hours, making it the strongest known gravitational wave source ($\log h=-20.78$) in the mHz regime. Because of its orbital period and total mass, WD 1242$-$105 is predicted to merge via gravitational radiation on a timescale of 740 Myr, which will most likely not result in a catastrophic explosion.

arXiv comment22 pages, 5 figures, 2 tables; to appear in Astronomical Journal

References in corpus (40)

• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Galaxy Evolution Explorer: A Space Ultraviolet Survey Mission
• The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
• Optimal Techniques in Two-dimensional Spectroscopy: Background Subtraction for the 21st Century
• The Formation Rate, Mass and Luminosity Functions of DA White Dwarfs from the Palomar Green Survey
• Low-frequency gravitational-wave science with eLISA/NGO
• A Catalog of Spectroscopically Confirmed White Dwarfs from the Sloan Digital Sky Survey Data Release 4
• A Spectroscopic Survey & Analysis of Bright, Hydrogen-Rich White Dwarfs
• Mass Transfer between Double White Dwarfs
• Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
• Surface Detonations in Double Degenerate Binary Systems Triggered by Accretion Stream Instabilities
• The Evolution of Early-Type Galaxies in Distant Clusters II: Internal Kinematics of 55 Galaxies in the z=0.33 Cluster CL1358+62
• Know Your Neighborhood: A Detailed Model Atmosphere Analysis of Nearby White Dwarfs
• Spectroscopic analysis of DA white dwarfs with 3D model atmospheres
• The ELM Survey. I. A Complete Sample of Extremely Low Mass White Dwarfs
• Thermonuclear .Ia Supernovae from Helium Shell Detonations: Explosion Models and Observables
• The structure and fate of white dwarf merger remnants
• High-resolution UVES/VLT spectra of white dwarfs observed for the ESO SN Ia Progenitor Survey. III. DA white dwarfs
• 2D simulations of the double-detonation model for thermonuclear transients from low-mass carbon-oxygen white dwarfs
• Search for progenitors of supnernovae type Ia with SPY
• Diffusion and the occurrence of hydrogen shell flashes in helium white dwarf stars
• The ELM Survey. IV. 24 White Dwarf Merger Systems
• Binaries discovered by the SPY project. IV. Five single-lined DA double white dwarfs
• The ELM Survey. V. Merging Massive White Dwarf Binaries
• The fraction of double degenerates among DA white dwarfs
• HST/FGS Parallaxes of AM CVn Stars and Astrophysical Consequences
• Precise Atmospheric Parameters for the Shortest Period Binary White Dwarfs: Gravitational Waves, Metals, and Pulsations
• The Discovery of Binary White Dwarfs that will Merge within 500 Myr
• Spectroscopic Identification of Cool White Dwarfs in the Solar Neighbourhood
• The triple degenerate star WD1704+481
• The White Dwarfs within 25 Parsecs of the Sun: Kinematics and Spectroscopic Subtypes
• Binaries discovered by the SPY project. II. HE 1414-0848: a double degenerate with a mass close to the Chandrasekhar limit
• Precise parameters for both white dwarfs in the eclipsing binary CSS 41177
• Observational Constraints on the Degenerate Mass-Radius Relation
• Classifying Luyten Stars Using An Optical-Infrared Reduced Proper Motion Diagram
• Astrometry and radial velocities of the planet host M dwarf GJ 317: new trigonometric distance, metallicity and upper limit to the mass of GJ 317b
• A New Gravitational Wave Verification Source
• Post-common-envelope binaries from SDSS. XIII: Mass dependencies of the orbital period distribution
• The Carnegie Astrometric Planet Search Program
• Binaries discovered by the SPY project. III. HE2209-1444: a massive, short period double degenerate

Cited by in corpus (16)

• Hot subluminous stars
• Prospects for detection of detached double white dwarf binaries with Gaia, LSST and LISA
• LISA verification binaries with updated distances from Gaia Data Release 2
• The binarity of the local white dwarf population
• Measurements of Physical Parameters of White Dwarfs: A Test of the Mass-Radius Relation
• The ELM Survey. VI. Eleven New Double Degenerates
• Most Double Degenerate Low Mass White Dwarf Binaries Merge
• The Solar Neighborhood. XXXIX. Parallax Results from the CTIOPI and NOFS Programs: 50 New Members of the 25 Parsec White Dwarf Sample
• A Catalogue of Potential Post Common Envelope Binaries
• Convection and Spin-Up During Common Envelope Evolution: The Formation of Short-Period Double White Dwarfs
• Influence of a mass transfer stability criterion on double white dwarf populations
• Two new Double-lined Spectroscopic Binary White Dwarfs
• A Gemini Snapshot Survey for Double Degenerates
• The Double Dust Envelopes of R Coronae Borealis Stars
• Massive Double White Dwarfs and the AM CVn Birthrate
• The evolution of relative frequencies of ONe and CO SNe Ia