J/ApJ/892/L35 He+He white dwarf SDSS J232230.20+050942.0 RVels (Brown+, 2020)
A 1201s orbital period detached binary: the first double helium core white
dwarf LISA verification binary.
Brown W.R., Kilic M., Bedard A., Kosakowski A., Bergeron P.
<Astrophys. J., 892, L35 (2020)>
=2020ApJ...892L..35B 2020ApJ...892L..35B
ADC_Keywords: Binaries, spectroscopic; Stars, white dwarf; Radial velocities;
Optical
Keywords: Compact binary stars; DA stars; DC stars; Gravitational wave sources;
Gravitational waves; White dwarf stars; Compact objects;
Detached binary stars
Abstract:
We report the discovery of a 1201s orbital period binary, the third
shortest-period detached binary known. Sloan Digital Sky Survey
J232230.20+050942.06 contains two He-core white dwarfs orbiting with a
27° inclination. Located 0.76kpc from the Sun, the binary has an
estimated Laser Interferometer Space Antenna (LISA) 4yr
signal-to-noise ratio of 40. J2322+0509 is the first He+He white dwarf
LISA verification binary, a source class that is predicted to account
for one-third of resolved LISA ultra-compact binary detections.
Description:
We targeted SDSSJ232230.20+050942.06 on the basis of its Gaia parallax
and Sloan Digital Sky Survey (SDSS) colors.
We obtained an exploratory spectrum of J2322+0509 on UT 2018-Dec-9 to
determine its stellar nature. We used the Blue Channel spectrograph on
the 6.5m MMT telescope. The following year we obtained time-series MMT
Blue Channel spectroscopy.
Finally, on UT 2019 November 20, we obtained 1hr of MagE spectroscopy
on the 6.5m Magellan Baade telescope.
We obtained time-series photometry of J2322+0509 using the 8m Gemini
North telescope with the Gemini Multi-Object Spectrograph on UT 2019
October 24 as part of the Director's Discretionary Time program
GN-2019B-DD-201.
Objects:
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RA (ICRS) DE Designation(s)
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23 22 30.19 +05 09 42.2 J2322+0509 = SDSS J232230.20+050942.0
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig1.dat 29 74 Radial velocities phased to the best-fit
orbital solution
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See also:
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/ApJ/743/138 : Spectroscopic survey of bright white dwarfs (Gianninas+, 2011)
J/ApJ/750/99 : The Pan-STARRS1 photometric system (Tonry+, 2012)
J/A+A/557/A19 : Mass and age of extreme low-mass white dwarfs (Althaus+, 2013)
J/ApJ/812/167 : The ELM survey. VI. 11 new ELM WD binaries (Gianninas+, 2015)
J/A+A/595/A35 : Low-mass helium WDs evolutionary models (Istrate+, 2016)
J/ApJ/848/11 : Spectroscopic and photometric analysis of WDs (Bedard+, 2017)
J/ApJ/889/49 : The ELM Survey. VIII. Final double WD binaries (Brown+, 2020)
Byte-by-byte Description of file: fig1.dat
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Bytes Format Units Label Explanations
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1- 11 F11.7 d BJD Barycentric Julian Date (TDB) at mid-exposure,
BJD-2458000
13- 19 F7.2 km/s RV [-222/209] Barycentric radial velocity
21- 25 F5.2 km/s e_RV [12.9/56.3] Uncertainty in RV
27- 29 I3 s Exp [150/480] Exposure time
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 17-Aug-2021