J/ApJ/984/58 Stellar parameters from XP and RVS spectra (Huson+, 2025)
Gaia Net: Toward Robust Spectroscopic Parameters of Stars of all
Evolutionary Stages.
Huson D., Cowan I., Sizemore L., Kounkel M., Hutchinson B.
<Astrophys. J. 984, 58 (2025)>
=2025ApJ...984...58H 2025ApJ...984...58H (SIMBAD/NED BibCode)
ADC_Keywords: Populations, stellar ; Effective temperatures ;
Abundances, [Fe/H] ; Optical ; Spectroscopy
Keywords: spectroscopy - stellar properties - surface gravity -
stellar populations
Abstract:
We present a new processing of XP spectra for 220 million stars
released in Gaia DR3. The new data model is capable of handling
objects with Teff between 2000 and 50000K and with between 0 and 10,
including objects of multitude of masses and evolutionary stages. This
includes for the first time ever robust processing of spectroscopic
parameters for pre-main-sequence stars, with sensitivity toward their
age. Through this analysis we examine the distribution of young
low-mass stars with ages of up to 20 Myr in the solar neighborhood,
and we identify a new massive (>1000 stars) population, Ophion, which
is found east of Sco-Cen. This population appears to be fully
disrupted, with negligible kinematic coherence. Nonetheless, due its
young age it appears to still persist as a spatial overdensity.
Through improved determination of ages of the nearby stars, it may be
possible to better recover the star-forming history of the solar
neighborhood outside of the moving groups.
Description:
We have developed a new pipeline, Gaia Net, for reprocessing Gaia XP
spectra that is capable of operating across the entire parameter space
of Teff and logg, from M&L dwarfs to O stars, from white dwarfs to
supergiants.
We present the results for 219196764 XP spectra and 999645 RVS spectra.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 78 219196764 Stellar Parameters Derived from XP Spectra
table2.dat 78 999645 Stellar Parameters Derived from RVS Spectra
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: table?.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR3 Gaia DR3 unique identifier
21- 30 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000)
32- 41 F10.6 deg DEdeg Declination in decimal degrees (J2000)
43- 47 F5.3 [K] logTeff log effective temperature
49- 53 F5.3 [K] e_logTeff Uncertainty in logTeff
55- 59 F5.2 [cm/s2] log(g) log surface gravity
61- 65 F5.2 [cm/s2] e_log(g) Uncertainty in log(g)
67- 71 F5.2 [Sun] [Fe/H] Metallicity
73- 77 F5.2 [Sun] e_[Fe/H] Uncertainty in [Fe/H]
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 25-Sep-2025