Publication
Title
Gaia Data Release 3 : hot-star radial velocities
Author
Abstract
Context. The second Gaia data release, DR2, contained radial velocities of stars with effective temperatures up to T-eff = 6900 K. The third data release, Gaia DR3, extends this up to T-eff = 14 500 K. Aims. We derive the radial velocities for hot stars (i.e., in the T-eff = 6900 14 500K range) from data obtained with the Radial Velocity Spectrometer (RVS) on board Gaia. Methods. The radial velocities were determined by the standard technique of measuring the Doppler shift of a template spectrum that was compared to the observed spectrum. The RVS wavelength range is very limited. The proximity to and systematic blueward offset of the calcium infrared triplet to the hydrogen Paschen lines in hot stars can result in a systematic offset in radial velocity. For the hot stars, we developed a specific code to improve the selection of the template spectrum, thereby avoiding this systematic offset. Results. With the improved code, and with the correction we propose to the DR3 archive radial velocities, we obtain values that agree with reference values to within 3 km s(-1) (in median). Because of the required S /N for applying the improved code, the hot star radial velocities in DR3 are mostly limited to stars with a magnitude in the RVS wavelength band similar to 12 mag.
Language
English
Source (journal)
Astronomy and astrophysics. - Berlin, 1969, currens
Publication
Berlin : Springer , 2023
ISSN
0004-6361 [print]
1432-0746 [online]
DOI
10.1051/0004-6361/202243685
Volume/pages
674 (2023) , p. 1-12
Article Reference
A7
ISI
001024440700007
Medium
E-only publicatie
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 02.10.2023
Last edited 25.04.2024
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