Gaia Spectroscopic Orbits Validated with LAMOST and GALAH Radial Velocities

Abstract

The recently published Gaia DR3 catalog of 181327 spectroscopic binaries (SB) includes the Keplerian elements of each orbit but not the measured radial velocities (RVs) and their epochs. Instead, the catalog lists a few parameters that characterize the robustness of each solution. In this work, we use two external sources to validate the orbits - 17563 LAMOST DR6 and 6018 GALAH DR3 stars with measured RVs that have Gaia-SB orbits. We compare the expected RVs, based on the Gaia orbits, with the LAMOST and GALAH measurements. Finding some orbits that are inconsistent with these measurements, we constructed a function that estimates the probability of each of the Gaia orbits to be correct, using the published robust parameters. We devise a clean but still very large Gaia SB1 sample of 91740 orbits. The sample differs from the parent sample by the absence of - physically unlikely and hence presumably spurious - short-period binaries with high eccentricity. The clean SB1 sample offers the prospect of thorough statistical studies of the binary population after carefully modeling of the remaining selection effects. At a first look, two possible features emerge from the clean sample - a paucity of short-period binaries with low-mass primaries, which might be a result of some observational bias, and a sub-sample of main-sequence binaries on circular orbits, probable evidence for circularization processes.

16 pages, 16 figures, accepted for publication in MNRAS

References in corpus (11)

• The GALAH+ Survey: Third Data Release
• The Zwicky Transient Facility Catalog of Periodic Variable Stars
• Barium & related stars and their white-dwarf companions I. Giant stars
• Tidal dissipation due to inertial waves can explain the circularization periods of solar-type binaries
• Variability, periodicity and contact binaries in WISE
• The Value-Added Catalog of ASAS-SN Eclipsing Binaries: Parameters of Thirty Thousand Detached Systems
• The circularization timescales of late-type binary stars
• Mass-ratio distribution of extremely low-mass white dwarf binaries
• Study of the mass-ratio distribution of spectroscopic binaries. I. A novel algorithm
• Study of the Mass-Ratio Distribution of Spectroscopic Binaries. II. The Boundaries of the Brown-Dwarf Desert as Seen with the APOGEE Spectroscopic Binaries
• Impact of Magnetic Braking on High-mass Close Binary Formation

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• Search for a Black Hole Binary in Gaia DR3 Astrometric Binary Stars with Spectroscopic Data
• Features of Gaia DR3 Spectroscopic Binaries I. Tidal circularization of Main-Sequence Stars
• Gaia Data Release 3: spectroscopic binary-star orbital solutions. The SB1 processing chain
• Newly identified compact hierarchical triple system candidates using Gaia DR3
• Spectroscopic Orbits of Subsystems in Multiple Stars. X (Summary)
• The Value-Added Catalog of ASAS-SN Eclipsing Binaries III: Masses and Radii of Gaia Spectroscopic Binaries
• High mass function ellipsoidal variables in the Gaia Focused Product Release: searching for black hole candidates in the binary zoo
• The Gaia-ESO Survey DR5.1 and Gaia DR3 GSP-Spec: a comparative analysis
• An upper limit on the frequency of short-period black hole companions to Sun-like stars
• Rotationally Driven Ultraviolet Emission of Red Giant Stars II. Metallicity, Activity, Binarity and Sub-subgiants