J/ApJS/273/12 Metal-poor stars in the MW from SMSS & SAGES (Hong+, 2024)
Candidate members of the VMP/EMP disk system of the galaxy from the SkyMapper
and SAGES surveys.
Hong J., Beers T.C., Lee Y.S., Huang Y., Hirai Y., Cabrera Garcia J.,
Shank D., Xu S., Yuan H., Mardini M.K., Catapano T., Zhao G., Fan Z.,
Zheng J., Wang W., Tan K., Zhao J., Li C.
<Astrophys. J. Suppl. Ser., 273, 12 (2024)>
=2024ApJS..273...12H 2024ApJS..273...12H
ADC_Keywords: Milky Way; Stars, metal-deficient; Surveys; Radial velocities;
Abundances, [Fe/H]; Stars, distances; Rotational velocities;
Optical
Keywords: Milky Way Galaxy ; Milky Way dynamics ; Milky Way disk ;
Milky Way evolution ; Milky Way formation ; Galactic archaeology
Abstract:
Photometric stellar surveys now cover a large fraction of the sky,
probe to fainter magnitudes than large-scale spectroscopic surveys,
and are relatively free from the target selection biases often
associated with such studies. Photometric-metallicity estimates that
include narrow/medium-band filters can achieve comparable accuracy and
precision to existing low-resolution spectroscopic surveys such as
Sloan Digital Sky Survey/SEGUE and LAMOST. Here we report on an effort
to identify likely members of the Galactic disk system among the very
metal-poor (VMP; [Fe/H]≤-2) and extremely metal-poor (EMP;
[Fe/H]≤-3) stars. Our analysis is based on an initial sample of
∼11.5 million stars with full space motions selected from the
SkyMapper Southern Survey (SMSS) and Stellar Abundance and Galactic
Evolution Survey (SAGES). After applying a number of quality cuts to
obtain the best available metallicity and dynamical estimates, we
analyze a total of ∼5.86 million stars in the combined SMSS/SAGES
sample. We employ two techniques that, depending on the method,
identify between 876 and 1476 VMP stars (6.9%-11.7% of all VMP stars)
and between 40 and 59 EMP stars (12.4%-18.3% of all EMP stars) that
appear to be members of the Galactic disk system on highly prograde
orbits (Vφ>150km/s). The total number of candidate VMP/EMP
disklike stars is 1496, the majority of which have low orbital
eccentricities, ecc≤0.4; many have ecc≤0.2. The large fractions of
VMP/EMP stars associated with the Milky Way disk system strongly
suggest the presence of an early-forming "primordial" disk.
Description:
Huang+ (2022ApJ...925..164H 2022ApJ...925..164H) derived stellar parameters, including
metallicity estimates, for more than 19 million dwarfs and 5 million
giants over essentially the entire Southern Hemisphere from SkyMapper
Southern Survey (SMSS) DR2, including about 731000 very metal-poor
(VMP) and 27000 extremely metal-poor (EMP) stars. If we restrict their
sample to stars with available radial velocities from Gaia DR3 (I/355)
and other sources, the number of stars is about 7.4 million, including
roughly 56000 VMP and 2300 EMP stars.
Huang+ (2023ApJ...957...65H 2023ApJ...957...65H) used a similar approach to Huang+ (2022)
and obtained effective temperatures, luminosity classifications based
on surface gravity, and metallicity estimates for over 26 million
stars, including some 874000 VMP and 13000 EMP stars from SAGES DR1
(Fan+ 2023ApJS..268....9F 2023ApJS..268....9F). About 4.1 million stars in this catalog
have available RVs, including roughly 41000 VMP and 1900 EMP stars.
Orbital parameters for the stars in our combined sample are determined
using their 6D astrometric parameters (positions, RVs, proper motions,
and distance estimates from Huang+ 2022ApJ...925..164H 2022ApJ...925..164H and
2023ApJ...957...65H 2023ApJ...957...65H), as well as their corresponding errors, as inputs
to the Action-based GAlaxy Modelling Architecture (AGAMA) package
(Vasiliev 2019MNRAS.482.1525V 2019MNRAS.482.1525V), adopting the solar positions and
peculiar motions described in Shank+ (2022, J/ApJS/261/19), and the
gravitational potential MW2017 (McMillan 2017MNRAS.465...76M 2017MNRAS.465...76M).
See Section 2.2.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 387 1291424 Candidate VMP/EMP stars in the combined
SMSS/SAGES sample
tablea2.dat 114 1496 1496 VMP/EMP disk-like candidate stars in the
combined SMSS/SAGES sample
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See also:
III/204 : Stellar radial velocities bibliographic catalog (Malaroda+, 2000)
III/213 : General Catalog of mean radial velocities (Barbier-Brossat+, 2000)
III/279 : RAVE 5th data release (Kunder+, 2017)
V/156 : LAMOST DR7 catalogs (Luo+, 2019)
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
III/286 : APOGEE-2 DR17 final allStar catalog (Abdurro'uf+, 2022)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
II/379 : SkyMapper Southern Sky Survey. DR4 (Onken+, 2024)
J/AJ/90/2089 : Stars of very low metal abundance. I (Beers+, 1985)
J/AJ/103/1987 : Stars of very low metal abundance (Beers+ 1992)
J/AJ/137/4377 : List of SEGUE plate pairs (Yanny+, 2009)
J/ApJ/794/58 : Metal-poor stars in the thick disk of the Gal (Beers+, 2014)
J/ApJ/797/21 : Carbon-enhanced metal-poor stars (Placco+, 2014)
J/MNRAS/454/2863 : Teff against colours calibrations (Huang+, 2015)
J/ApJ/833/20 : Carbon-enhanced metal-poor (CEMP) star abund. (Yoon+, 2016)
J/MNRAS/497/L7 : Gal. disc Pristine low-metallicity stars (Sestito+, 2020)
J/MNRAS/492/3241 : The Pristine survey. IX. (Venn+, 2020)
J/MNRAS/503/2539 : Galaxy halo Extremely Metal-Poor stars (Cordoni+, 2021)
J/ApJ/913/11 : Sp. follow-up of bright metal-poor stars (Limberg+, 2021)
J/ApJ/931/147 : Very metal-poor stars with LAMOST & Subaru. II. (Li+, 2022)
J/ApJS/262/8 : Sp. of low-metallicity S-PLUS stars (Placco+, 2022)
J/ApJS/259/60 : SEGUE-2 updated stellar parameter pipeline (Rockosi+, 2022)
J/ApJS/261/19 : DTGs of metal-poor stars. II. RAVE DR6 (Shank+, 2022)
J/A+A/674/A194 : Gal. giant stars photometric metallicity (Bellazzini+, 2023)
J/A+A/674/A33 : Gaia synthetic phot. cat. of white dwarfs (Gaia Coll., 2023)
J/A+A/683/L11 : Bright VPM stars from Gaia RVS spectra (Viswanathan+, 2024)
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 source ID (source_id)
21- 22 I2 h RAh Hour of Right Ascension (J2000) (1)
24- 25 I2 min RAm Minute of Right Ascension (J2000) (1)
27- 31 F5.2 s RAs Second of Right Ascension (J2000) (1)
33 A1 --- DE- Sign of the Declination (J2000) (1)
34- 35 I2 deg DEd Degree of Declination (J2000) (1)
37- 38 I2 arcmin DEm Arcminute of Declination (J2000) (1)
40- 43 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
45- 50 F6.3 mag GmagC [4.5/20] Corrected Gaia DR3 G-band
magnitude (G_C) (2)
52- 56 F5.3 mag e_GmagC [0.003/0.02] Uncertainty in GmagC
(errGC) (2)
58- 62 F5.3 mag B-R0 [0.56/1.8] Intrinsic Gaia DR3 BP-RP
color (br0) (2)
64- 68 F5.3 mag e_B-R0 [0.005/0.07] Uncertainty in BR0
(err_br0) (2)
70- 74 F5.3 mag E(B-V) [0.001/0.5] Optical color excess,
Schlegel+ 1998ApJ...500..525S 1998ApJ...500..525S
(ebv_sfd) (3)
76- 80 F5.2 [-] FeH-UB [-3.42/0.64]? Photometric-metallicity
estimate based on u-Gaia BP
(feh-ub) (2)
82- 85 F4.2 [-] e_FeH-UB [0/1.4]? Uncertainty in FeH-UB
(err_feh-ub) (2)
87- 91 F5.2 [-] FeH-VB [-3.51/0.63]? Photometric-metallicity
estimate based on v-Gaia BP
(feh-vb) (2)
93- 96 F4.2 [-] e_FeH-VB [0.01/1.4]? Uncertainty in FeH-VB
(err_feh-vb) (2)
98- 102 F5.2 [-] FeH-UVB [-3.52/0.64]? Photometric-metallicity
estimate based on combination of
colors (feh-uvb) (2)
104- 107 F4.2 [-] e_FeH-UVB [0/1.4]? Uncertainty in FeH
(err_feh-uvb) (2)
109- 112 I4 K Teff [3830/6669] Effective temperature (2)
114- 116 I3 K e_Teff [50/425] Uncertainty in Teff
(err_Teff) (2)
118- 122 F5.2 kpc Dist [0.02/72] Distance (dist_adop) (2)(3)
124- 128 F5.2 kpc e_Dist [0/29] Uncertainty in Dist
(errdistadop) (2)(3)
130- 145 A16 --- f_Dist Type of Distance estimate
(distadopflg) (2)(3)
147- 152 F6.1 km.s-1 RVel [-798/897] Radial Velocity (rv_adop)
(2)
154- 157 F4.1 km.s-1 e_RVel [0/98] Uncertainty in RVel
(errrvadop) (2)
159- 166 A8 --- f_RVel Type or Source of RVel (rvadopflg)
(2)(4)
168- 172 F5.2 mas plx [-1.1/43.1] Gaia DR3 parallax
(parallax)
174- 177 F4.2 mas e_plx [0.01/0.6] Gaia DR3 parallax
uncertainty (parallax_error)
179- 184 F6.1 mas.yr-1 pmRA [-139/147.5] Gaia DR3 proper motion
in RA
186- 188 F3.1 mas.yr-1 e_pmRA [0/0.6] Uncertainty in pmRA
(pmra_error)
190- 195 F6.1 mas.yr-1 pmDE [-154.2/109] Gaia DR3 proper motion
in DE (pmdec)
197- 199 F3.1 mas.yr-1 e_pmDE [0/0.6] Uncertainty in pmDE
(pmdec_error)
201- 204 F4.1 --- pmRApmDEcor [-1/0.9] Correlation between proper
motion in RA and DE
206- 210 A5 --- Type Type, D=Dwarf; G=Giant (2)
212- 214 A3 --- SubType SubType, TO=Turn-off stars;
MS=main-sequence stars (2)
216- 223 F8.1 km.s-1 vPHI [-18780/3913] Rotational velocity,
AGAMA
225- 230 F6.1 km.s-1 e_vPHI [0/3074] Uncertainty in vPHI
232- 242 F11.1 km2.s-2 E [-248428/179709105] Orbital energy,
AGAMA
244- 250 F7.1 km2.s-2 e_E [0/83216] Uncertainty in E
252- 260 F9.1 kpc.km.s-1 Jr [-1/5138400] Cylindrical action in
radius, AGAMA
262- 270 F9.1 kpc.km.s-1 e_Jr [0/1590553] Uncertainty in Jr
272- 280 F9.1 kpc.km.s-1 Jphi [-761649/132643] Cylindrical action
in rotation, AGAMA
282- 289 F8.1 kpc.km.s-1 e_Jphi [0/203858] Uncertainty in Jphi
291- 297 F7.1 kpc.km.s-1 Jz [-1/13854] Cylindrical action in
height, AGAMA
299- 304 F6.1 kpc.km.s-1 e_Jz [0/6887] Uncertainty in Jz
306- 309 F4.1 kpc rperi [0/74.2] Galactic pericentric
distance, AGAMA
311- 314 F4.1 kpc e_rperi [0/33] Uncertainty in rperi
316- 323 F8.1 kpc rapo [1.5/189578] Galactic apocentric
distance, AGAMA
325- 331 F7.1 kpc e_rapo [0/30729] Uncertainty in rapo
333- 339 F7.1 kpc Zmax [0/59123] Maximum height above the
Galactic plane, AGAMA
341- 347 F7.1 kpc e_Zmax [0/16450] Uncertainty in Zmax
349- 354 F6.1 --- relerr-Zmax [0/2780] Relative uncertainty of the
maximum height above the Galactic
plane
356- 363 F8.1 kpc Rmax [0/187955] Projected Galactic
apocentric distance, AGAMA (5)
365- 368 F4.2 --- relerr-Rmax [0/1]? Relative uncertainty of the
projected Galactic apocentric
distance
370- 373 F4.2 rad inc [0/1.6] Inclination angle (6)
375- 379 F5.3 --- ecc [0/1] Eccentricity, AGAMA
381- 387 A7 --- Crit Criterion for halo, thick, or thin
disk-like orbits (7)
--------------------------------------------------------------------------------
Note (1): Positions from SMSS DR2 and SAGES DR1 and are given in
reference frame J2000 at epoch=J2000.
Note (2): GmagC, BR0, Type, Teff, Dist, and RVel, measurements
are provided by Huang+ 2022ApJ...925..164H 2022ApJ...925..164H & 2023ApJ...957...65H 2023ApJ...957...65H as
found on NADC/China-VO: http://doi.org/10.12149/101074.
FeH-# values are also from the same source, but have been disaggregated
from the original feh, err_feh, and feh_flg values in the Huang+ dataset.
Note (3): Derived by "parallax" or by color-absolute magnitude fiducial
relations from Huang+ 2022ApJ...925..164H 2022ApJ...925..164H ; 2023ApJ...957...65H 2023ApJ...957...65H
Note (4): Type or Source of RVel as follows:
AEGIS = Yoon+ 2018ApJ...861..146Y 2018ApJ...861..146Y, collected in Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
APG-DR17 = Abdurro'uf+ (2022, III/286), collected in Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
APOGEE = Abdurro'uf+ (2022, III/286), collected in Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
and 2023ApJ...957...65H 2023ApJ...957...65H
GALAH = Buder+ 2021, J/MNRAS/506/150, collected in
Huang+ 2022ApJ...925..164H 2022ApJ...925..164H and 2023ApJ...957...65H 2023ApJ...957...65H
GaiaDR3 = Gaia DR3 radial velocity (Katz+ 2023A&A...674A...5K 2023A&A...674A...5K), collected
in Huang+ 2022ApJ...925..164H 2022ApJ...925..164H and 2023ApJ...957...65H 2023ApJ...957...65H
Gaia = Gaia DR2 (Katz+ 2019A&A...622A.205K 2019A&A...622A.205K), collected in
Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
Gaia-ESO = Gaia-ESO DR3 (Gilmore+ 2012Msngr.147...25G 2012Msngr.147...25G;
Randich & Gilmore 2013Msngr.154...47R 2013Msngr.154...47R), collected in
Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
LAMOST = LAMOST DR7, collected in Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
and 2023ApJ...957...65H 2023ApJ...957...65H
LIT = Literature sources including,
Barbier-Brossat & Figon (2000, III/213), Malaroda+ (2000, III/204),
and de Bruijne & Eilers (2012, J/A+A/546/A61), collected in
Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
LM-DR9 = LAMOST DR9, collected in Huang+ 2022ApJ...925..164H 2022ApJ...925..164H
RAVE = RAVE DR5 (Kunder+ 2017, III/279), collected in
Huang+ 2022ApJ...925..164H 2022ApJ...925..164H and 2023ApJ...957...65H 2023ApJ...957...65H
SEGUE = SDSS/SEGUE DR16 (Ahumada+ 2020, V/154), collected in
Huang+ 2022ApJ...925..164H 2022ApJ...925..164H and 2023ApJ...957...65H 2023ApJ...957...65H
Note (5): Projection of the Galactic apocentric distance onto
the Galactic plane as given by Rmax2=rapo2-Zmax2.
Note (6): Defined as arctangent of Zmax/Rmax
Note (7): Flag with "Zmax", "Haywood", or "Both" to indicate the
criterion used for the separation of stars on halo-like orbits
from those on thick-disk like and thin-disk like orbits.
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 source ID (source_id)
21- 22 I2 h RAh Hour of Right Ascension (J2000) (1)
24- 25 I2 min RAm Minute of Right Ascension (J2000) (1)
27- 31 F5.2 s RAs Second of Right Ascension (J2000) (1)
33 A1 --- DE- Sign of the Declination (J2000) (1)
34- 35 I2 deg DEd Degree of Declination (J2000) (1)
37- 38 I2 arcmin DEm Arcminute of Declination (J2000) (1)
40- 43 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
45- 50 F6.3 mag GmagC [8.9/19] Corrected Gaia DR3 G-band magnitude
(2)
52- 56 F5.3 mag B-R0 [0.57/1.62] Intrinsic Gaia DR3 BP-RP color (2)
58 A1 --- Type Type, D=Dwarf; G=Giant (2)
60- 64 F5.2 kpc Dist [0.26/19.12] Distance (3)
66- 70 F5.2 [-] FeH [-3.51/-2] Photometric-metallicity estimate
(4)
72- 75 F4.2 [-] e_FeH [0.01/0.5] Uncertainty in FeH (2)(4)
77- 81 F5.1 km.s-1 vPHI [150/612] Rotational velocity, AGAMA
83- 88 F6.1 kpc Zmax [0.1/1181] Maximum height above the Galactic
plane, AGAMA
90- 95 F6.1 kpc Rmax [1.3/3332] Projected Galactic apocentric
distance, AGAMA (5)
97- 100 F4.2 rad inc [0.02/1.2] Inclination angle (6)
102- 106 F5.3 --- ecc [0.005/1] Eccentricity, AGAMA
108- 114 A7 --- Crit Criterion for halo, thick, or thin disk-like
orbits (7)
--------------------------------------------------------------------------------
Note (1): Positions from SMSS DR2 and SAGES DR1 and are given in
reference frame J2000 at epoch=J2000.
Note (2): GmagC, BR0, Type, Dist, and FeH are provided by
Huang+ 2022ApJ...925..164H 2022ApJ...925..164H and 2023ApJ...957...65H 2023ApJ...957...65H as found on
NADC/China-VO: http://doi.org/10.12149/101074
Note (3): The type of distance is given in Table A1
Note (4): Metallicity of the final sample this table is based on
FEH-VB and FEH-UVB of Table A1 after applying the cuts for the
metallicity.
Note (5): Projection of the Galactic apocentric distance onto
the Galactic plane as given by Rmax2=rapo2-Zmax2.
Note (6): Defined as arctangent of Zmax/Rmax
Note (7): Flag with "Zmax", "Haywood", or "Both" to indicate the
criterion used for the separation of stars on halo-like orbits
from those on thick-disk like and thin-disk like orbits.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 26-Nov-2024