Radial velocities for the Hipparcos-Gaia Hundred-Thousand-Proper-Motion project

Abstract

(abridged) The Hundred-Thousand-Proper-Motion (HTPM) project will determine the proper motions of ~113500 stars using a 23-year baseline. The proper motions will use the Hipparcos data, with epoch 1991.25, as first epoch and the first intermediate-release Gaia astrometry, with epoch ~2014.5, as second epoch. The expected HTPM proper-motion standard errors are 30-190 muas/yr, depending on stellar magnitude. Depending on the characteristics of an object, in particular its distance and velocity, its radial velocity can have a significant impact on the determination of its proper motion. The impact of this perspective acceleration is largest for fast-moving, nearby stars. Our goal is to determine, for each star in the Hipparcos catalogue, the radial-velocity standard error that is required to guarantee a negligible contribution of perspective acceleration to the HTPM proper-motion precision. We employ two evaluation criteria, both based on Monte-Carlo simulations, with which we determine which stars need to be spectroscopically (re-)measured. Both criteria take the Hipparcos measurement errors into account. For each star in the Hipparcos catalogue, we determine the confidence level with which the available radial velocity and its standard error, taken from the XHIP compilation catalogue, are acceptable. We find that for 97 stars, the radial velocities available in the literature are insufficiently precise for a 68.27% confidence level. We also identify 109 stars for which radial velocities are currently unknown yet need to be acquired to meet the 68.27% confidence level. To satisfy the radial-velocity requirements coming from our study will be a daunting task consuming a significant amount of spectroscopic telescope time. Fortunately, the follow-up spectroscopy is not time-critical since the HTPM proper motions can be corrected a posteriori once (improved) radial velocities become available.

Accepted in A&A

References in corpus (3)

• PPM-Extended (PPMX) - a catalogue of positions and proper motions
• Displacement of the Sun from the Galactic Plane
• OB Stars in the Solar Neighborhood II: Kinematics

Cited by in corpus (20)

• The Gaia mission
• Gaia Data Release 1: Astrometry - one billion positions, two million proper motions and parallaxes
• Extracting Radial Velocities of A- and B-type Stars from Echelle Spectrograph Calibration Spectra
• BANYAN. IV. Fundamental parameters of low-mass star candidates in nearby young stellar kinematic groups - Isochronal Age determination using Magnetic evolutionary models
• BANYAN. IX. The Initial Mass Function and Planetary-Mass Object Space Density of the TW Hya Association
• Search for associations containing young stars (SACY). V. Is multiplicity universal? Tight multiple systems
• New Evidence for a Substellar Luminosity Problem: Dynamical Mass for the Brown Dwarf Binary Gl 417BC
• Joint astrometric solution of Hipparcos and Gaia: A recipe for the Hundred Thousand Proper Motions project
• Exocomet signatures around the A-shell star $\Phi$ Leo?
• Vetting Galactic Leavitt Law Calibrators using Radial Velocities: On the Variability, Binarity, and Possible Parallax Error of 19 Long-period Cepheids
• Rotation and Abundances of the Benchmark Brown Dwarf HD 33632 Ab from Keck/KPIC High-resolution Spectroscopy
• The Origin of B-Type Runaway Stars: Non-LTE Abundances as a Diagnostic
• Multiples among B stars in the Scorpius-Centaurus association
• Deep VLA Images of the HH 124 IRS Radio Cluster and its Surroundings and a New Determination of the Distance to NGC 2264
• Atomic Gas in Debris Discs
• Magnetic field structure in single late-type giants: The weak G-band giant 37 Comae from 2008 to 2011
• Searching for new young stars in the northern hemisphere: The Pisces Moving Group
• Understanding the angular momentum evolution of T Tauri and Herbig Ae/Be stars
• V410 Puppis: A useful laboratory for early stellar evolution
• A Search for Chemical Anomalies of Seven A-types Stars