The ELM Survey. VIII. Ninety-eight Double White Dwarf Binaries
Research output: Contribution to journal › Journal article › Research › peer-review
Documents
- Fulltext
Accepted author manuscript, 1.05 MB, PDF document
We present the final sample of 98 detached double white dwarf (WD) binaries found in the Extremely Low Mass (ELM) Survey, a spectroscopic survey targeting M He-core WDs completed in the Sloan Digital Sky Survey footprint. Over the course of the survey we observed ancillary low-mass WD candidates like GD 278, which we show is a P = 0.19 day double WD binary, as well as candidates that turn out to be field blue straggler/subdwarf A-type stars with luminosities too high to be WDs given their Gaia parallaxes. Here, we define a clean sample of ELM WDs that is complete within our target selection and magnitude range 15 g(0) P <1.5 day double WD binaries, 35% of which belong to the Galactic halo. We infer that these are mostly He+CO WD binaries given the measurement constraints. The merger rate of the observed He+CO WD binaries exceeds the formation rate of stable mass-transfer AM CVn binaries by a factor of 25, and so the majority of He+CO WD binaries must experience unstable mass transfer and merge. The systems with the shortest periods, such as J0651+2844, are signature LISA verification binaries that can be studied with gravitational waves and light.
Original language | English |
---|---|
Article number | 49 |
Journal | Astrophysical Journal |
Volume | 889 |
Issue number | 1 |
Number of pages | 17 |
ISSN | 0004-637X |
DOIs | |
Publication status | Published - 20 Jan 2020 |
- White dwarf stars, Compact binary stars, Galaxy stellar content, COMMON-ENVELOPE BINARIES, AM CVN STARS, NEUTRON-STAR, SDA PROBLEM, SDSS, POPULATION, CATALOG, SEARCH, SAMPLE, GAIA
Research areas
ID: 247498639