J/A+A/674/A194 Galactic giant stars photometric metallicity (Bellazzini+, 2023)
Photometric metallicity for 694233 Galactic giant stars from Gaia DR3 synthetic
Stromgren photometry. Metallicity distribution functions of halo sub-structures.
Bellazzini M., Massari D., De Angeli F., Mucciarelli A., Bragaglia. A,
Riello M., Montegriffo P.
<Astron. Astrophys. 674, A194 (2023)>
=2023A&A...674A.194B 2023A&A...674A.194B (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Stars, giant ; Abundances, [Fe/H] ; Photometry, uvby
Keywords: catalogs - techniques: photometric - stars: abundances -
Galaxy: structure - Galaxy: evolution - Galaxy: halo
Abstract:
We use the calibrations by Calamida et al. (2007ApJ...670..400C 2007ApJ...670..400C) and
by Hilker et al. (2000A&A...355..994H 2000A&A...355..994H), and the standardised synthetic
photometry in the v, b, and y Stromgren passbands from Gaia DR3 BP/RP
spectra, to obtain photometric metallicities for a selected sample of
694233 old Galactic giant stars having |b|>20.0 and parallax
uncertainties lower than 10%. The zero point of both sets of
photometric metallicities has been shifted to to ensure optimal match
with the spectroscopic [Fe/H] values for 44785 stars in common with
APOGEE DR17, focusing on the metallicity range where they provide the
highest accuracy. The metallicities derived in this way from the
Calamida et al. (2007ApJ...670..400C 2007ApJ...670..400C) calibration display a typical
accuracy of ∼0.1dex and 1 sigma precision ∼0.2dex in the range
-2.2≤[Fe/H]≤-0.4, while they show a systematic trend with [Fe/H] at
higher metallicity, beyond the applicability range of the relation.
Those derived from the Hilker et al. (2000A&A...355..994H 2000A&A...355..994H) calibration
display, in general, worse precision, and lower accuracy in the
metal-poor regime, but have a median accuracy <0.05dex for
[Fe/H]≥-0.8. These results are confirmed and, consequently, the
metallicities validated, by comparison with large sets of
spectroscopic metallicities from various surveys. The newly obtained
metallicities are used to derive metallicity distributions for several
previously identified sub-structures in the Galactic halo with an
unprecedented number of stars. The catalogue including both sets of
metallicities and the associated uncertainties is made publicly
available.
Description:
Photometric metallicities for 694233 old Galactic giant stars derived
from the Calamida et al. (2007ApJ...670..400C 2007ApJ...670..400C) calibration and the
from the Hilker (2000A&A...355..994H 2000A&A...355..994H) calibration of Stromgren m_1,0
index, re-calibrated on spectroscopic metallicities from APOGEE-DR17,
with associated uncertainties.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 52 694233 Photometric metallicities for 694233 stars
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR3 Gaia DR3 source id number
20- 26 F7.2 --- [Fe/H]C Metallicity from the C07 (Calamida et al.,
2007ApJ...670..400C 2007ApJ...670..400C) calibration (1)
27- 33 F7.2 --- e_[Fe/H]C Uncertainty on [Fe/H]C
34- 40 F7.2 --- [Fe/H]H Metallicity from the H00 (Hilker,
2000A&A...355..994H 2000A&A...355..994H) calibration (1)
41- 47 F7.2 --- e_[Fe/H]H Uncertainty on [Fe/H]H
52 A1 --- f_[Fe/H]H [0/1] Validity range flag for [Fe/H]H (2)
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Note (1): both [Fe/H]C and [Fe/H]H are re-calibrated on spectroscopic
metallicities from APOGEE DR17 (Ahumada et al., 2020ApJS..249....3A 2020ApJS..249....3A,
Cat. V/154).
Note (2): Validity range flag for [Fe/H]H as follows:
0 = star whose (b-y)0 colour is within the validity range of
the H00 (Hilker, 2000A&A...355..994H 2000A&A...355..994H) calibration.
1 = star whose (b-y)0 colour is slightly beyond the validity range
of the H00 (Hilker, 2000A&A...355..994H 2000A&A...355..994H) calibration.
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Acknowledgements:
Michele Bellazzini, michele.bellazzini(at)inaf.it
(End) Michele Bellazzini [INAF- OAS Bologna], Patricia Vannier [CDS] 20-Apr-2023