J/MNRAS/509/1664 Membership study of 70 stars clusters (Jackson+, 2022)
The Gaia-ESO Survey Membership probabilities for stars in 63 open and
7 globular clusters from 3D kinematics.
Jackson R.J., Jeffries R.D., Wright N.J., Randich S., Sacco G.,
Bragaglia A., Hourihane A., Tognelli E., Degl'Innocenti S.,
Prada Moroni P.G., Gilmore G., Bensby T., Pancino E., Smiljanic R.,
Bergemann M., Carraro G., Franciosini E., Gonneau A., Jofre P., Lewis J.,
Magrini L., Morbidelli L., Prisinzano L., Worley C., Zaggia S.,
Tautvaisiene G., Gutierrez Albarran M.L., Montes D., Jimenez-Esteban F.
<Mon. Not. R. Astron. Soc. 509, 1664-1680>
=2022MNRAS.509.1664J 2022MNRAS.509.1664J (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Clusters, globular ; Populations, stellar ;
Positional data ; Radial velocities ; Effective temperatures ;
Photometry, infrared ; Optical ; Spectroscopy
Keywords: stars: evolution - stars: pre-main-sequence -
open clusters and associations: general
Abstract:
Spectroscopy from the final internal data release of the Gaia-ESO
Survey (GES) has been combined with Gaia EDR3 to assign membership
probabilities to targets observed towards 63 Galactic open clusters
and 7 globular clusters. The membership probabilities are based
chiefly on maximum likelihood modelling of the 3D kinematics of the
targets, separating them into cluster and field populations. From 43
211 observed targets, 13985 are identified as highly probable cluster
members (P > 0.9), with an average membership probability of 0.993.
The addition of GES radial velocities successfully drives down the
fraction of false positives and we achieve better levels of
discrimination in most clusters over the use of astrometric data
alone, especially those at larger distances. Since the membership
selection is almost purely kinematic, the union of this catalogue with
GES and Gaia is ideal for investigating the photometric and chemical
properties of clusters as a function of stellar mass, age, and
Galactic position.
Description:
The Gaia-ESO Survey (GES) is a large public survey programme that
uses the multifibre FLAMES (Fiber Large Array Multi-Element
Spectrograph; Pasquini et al. 2002Msngr.110....1P 2002Msngr.110....1P) instrument on the
8-m UT2-Kueyen telescope of the Very Large Telescope (VLT) to perform
chemical and kinematical studies of Galactic stellar populations (see
Gilmore et al. 2012Msngr.147...25G 2012Msngr.147...25G; Randich & Gaia-ESO Consortium
2013Msngr.154...47R 2013Msngr.154...47R; Pancino et al. 2017). The GIRAFFE and UVES
(Ultraviolet and Visual Echelle Spectrograph; Dekker et al.
2000SPIE.4008..534D 2000SPIE.4008..534D) spectrographs attached to FLAMES, were used to
obtain spectra of about 105 and 104 stars.
The work presented here follows on from Randich et al.
(2018A&A...612A..99R 2018A&A...612A..99R, Cat. J/A+A/612/A99) and Jackson et al.
(2020MNRAS.496.4701J 2020MNRAS.496.4701J, Cat. J/MNRAS/496/4701), where Gaia astrometry
from Gaia DR1 and Gaia DR2, in the form of its first and second data
releases was used in conjunction with spectroscopic parameters from
earlier GES data releases to define samples of high probability
cluster members.Here, we use temperatures, gravities, and radial
velocities from GESiDR6, together with astrometry from Gaia EDR3
(Lindegren et al. 2021A&A...649A...2L 2021A&A...649A...2L), to define membership
probabilities for sources in 70 clusters from GES. These comprise the
full set of 60 open cluster targets in GES that were observed using
the GIRAFFE 665 nm spectrograph with the HR15N order-sorting filter or
with UVES 520nm and 580nm spectrograph to which we added one archival
cluster (M67) and 7 globular clusters that were also observed with
GIRAFFE+HR15N and homogeneously analysed as part of the GES project.
The table3.dat shows the full list of targets with HR15N and/or UVES
spectra that are common to the WG catalogue showing the WG 'cname'
together with cluster name, setup, and co-ordinates read from the
spectrum metadata. The are 41926 entries for 39441 unique targets. Of
these, 88 per cent have values of Teff derived by the GES WGs and
67 per cent have WG values of logg. The tablea2.dat lists a further
3770 targets common to our list of 70 clusters that were observed with
a variety of GIRAFFE setups but not with GIRAFFE + HR15N or UVES. In
the interests of homogeneity, these targets were excluded from the
main kinematic analysis but their individual membership probabilities
are estimated in Appendix A, (i.e also see the sections 2 Source data
and 3 Calculated parameters). For its part, cluster.dat resume the
name of the 70 clusters used in this study, the number of target
members for main and supplementary list.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
cluster.dat 20 70 Lists of the 70 clusters used in this study
table3.dat 141 41926 Membership probabilities for GESiDR6
cluster targets
tablea2.dat 124 3770 *Membership probabilities of supplementary
targets
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Note on tablea2.dat: This table lists a further 3770 targets common to our list
of 70 clusters that were observed with a variety of GIRAFFE setups but not
with GIRAFFE + HR15N or UVES. In the interests of homogeneity, these targets
were excluded from the main kinematic analysis but their individual membership
probabilities are estimated in the section Appendix A.
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See also:
J/A+A/612/A99 : Gaia-ESO Survey in 7 open star cluster fields
(Randich+,2018)
J/MNRAS/496/4701 : Gaia-ESO Survey: members of 32 open clusters (Jackson+,2020)
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
II/337 : VISTA Variables in the Via Lactea Survey DR1 (Saito+, 2012)
II/359 : The VISTA Hemisphere Survey (VHS) catalog DR4.1
(McMahon+, 2013)
II/367 : The VISTA Hemisphere Survey (VHS) catalog DR5
(McMahon+, 2020)
VII/233 : 2MASS All-Sky Extended Source Catalog XSC
(IPAC-UMass, 2003-2006)
J/A+A/533/A109 : Pisa pre-main sequence tracks and isochrones
(Tognelli+, 2011)
Byte-by-byte Description of file: cluster.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Cluster Name of the cluster (Cluster)
13- 16 I4 --- Number Number of targets in the table3 (Number)
18- 20 I3 --- Nbrsup ? Number of supplementary targets
in the tablea2 (Nbrsup)
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- ID Name of the target object (cname)
18- 28 A11 --- Cluster Name of the cluster (DBname)
30- 32 I3 nm Lambda Spectrograph setup (setup) (G1)
34- 43 F10.6 deg RAdeg Right ascension (RA) (J2000)
45- 54 F10.6 deg DEdeg Declination (Dec) (J2000)
56- 57 I2 --- f_ID ? Flag of the targets selection (Flag) (G2)
59- 65 F7.2 km/s RV ?=-999.00 Radial velocity (RV) (G3)
67- 73 F7.2 km/s e_RV ?=-999.00 Mean uncertainty on RV (e_RV)
75- 76 A2 --- --- [ID]
77- 95 I19 --- GaiaEDR3 Gaia EDR3 ID source (Gaia_ID) (G4)
97-103 F7.2 mag Gmag ?=-999.00 G-band mean magnitude (Vega)
from GaiaEDR3 (G)
105-109 I5 K Teff Effective temperature (Tpeff) (G5)
111-117 F7.2 mag Ksmag ?=-999.00 The 2MASS and-or VISTA KS band
apparent magnitude (KpS)
119-125 F7.2 [Lsun] logL* ?=-999.00 Logarithm of the stellar
luminosity (logL) (G6)
127-133 F7.4 --- P3D Membership probability P3D (P3D) (G7)
135-141 F7.4 --- PQG Membership probability PQG (PQG) (G7)
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Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- ID Name of the target object (cname)
18- 27 A10 --- Cluster Name of the cluster (DBname)
29- 38 F10.6 deg RAdeg Right ascension (RA) (J2000)
40- 49 F10.6 deg DEdeg Declination (Dec) (J2000)
51- 52 I2 --- f_ID ? Flag of the targets selection (Flag) (G2)
54- 60 F7.2 km/s RV ?=0. Radial velocity (RV) (G3)
62- 66 F5.2 km/s e_RV ?=-0. Mean uncertainty on RV (e_RV)
68- 69 A2 --- --- [ID]
70- 88 I19 --- GaiaEDR3 Gaia EDR3 ID source (Gaia_ID) (G4)
90- 95 F6.2 mag Gmag ?=999 G-band mean magnitude (Vega) from
GaiaEDR3 (G)
97-101 I5 K Teff ?=-999 Effective temperature (Tpeff) (G5)
103-108 F6.2 mag Ksmag ?=999 The 2MASS and-or VISTA KS band
apparent magnitude (KpS)
110-116 F7.2 [Lsun] logL* ?=-999. Logarithm of the stellar
luminosity (logL) (G6)
118-124 F7.4 --- P3D Membership probability P3D (P3D) (G7)
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Global notes:
Note (G1): Lambda setup are linked to spectrographs GIRAFFE and UVES as follows:
665 = GIRAFFE 665 nm (HR15N) order-sorting filter
520 = UVES 520 nm spectra associated
580 = UVES 580 nm spectra associated
Note (G2): Targets flagged are classified as explained in the section 3.1
Selecting potential cluster members as follows:
-1 = Targets with a large velocity offset relative to other cluster
members are stars with VRA , VDec , or RV outside a window
of ±75 km/s centred on the median velocity of the remaining
targets
0 = Targets that remain after the screening process and included
in the maximum likelihood analysis
1 = Background giants by logg are stars in clusters aged < 1 Gyr
which have logg =< 3.4, 4000 < Tpeff/K < 7000 and with
a parallax smaller (by at least 2σ) than a value
corresponding to the intrinsic distance modulus of the
cluster +2 mag
2 = Background giants by spectral indices
γ'= γ + τ/6 (defined in the section 2.2
Spectral indices) are stars where logg is undefined but the
modified index γ' => 1.335 and that meet the other
conditions of the first criteria (i.e see section 3.1 Selecting
potential cluster members, criteria i)
3 = Background targets by parallax are stars with a Gaia parallax
smaller by at least 4σ than a value corresponding to
the intrinsic distance modulus of the cluster +2 mag
Note (G3): Radial velocities acquisitions is available in the section 2.3 Radial
velocities. For GIRAFFE spectra, the radial velocities (RV) were read
from the spectrum velclass metadata. For UVES, the mean value of RV
was taken from values reported for the upper and lower CCD spectra
(Sacco et al. 2014A&A...565A.113S 2014A&A...565A.113S).
Note (G4): Details on cross-match with Gaia EDR3 (2021A&A...649A...1G 2021A&A...649A...1G,
Cat. I/350) to determine their astrometric properties and principle
photometric properties, available in the section 2.4 Near infrared
and Gaia data.
Note (G5): Details on Teff and KS acquisitions are available in the
section 2.5 Approximate values of γ, Teff and KS.
As γ' and log(g), Teff and KS were required for
all targets used in the membership analysis in order to identify
giants and estimate target luminosities and masses to model the
effects of binarity on cluster membership probability. Teff were
taken from GES Working Groups (WGs) and KS data are available
from 2MASS and/or VISTA sources for 95 per cent of targets.
Note (G6): As explained in the section 3.3 Target luminosity and mass,
the stellar luminosities logL were calculated from the KpS
magnitudes using bolometric corrections interpolated from the
Tpeff and photometry reported for updated solar metallicity of
Pisa model isochrones (Tognelli et al. 2011A&A...533A.109T 2011A&A...533A.109T, Cat.
J/A+A/533/A109).
Note (G7): As exposed in the sections 3.4 Probability of cluster membership and
4.3 Target membership probabilities, we computed two kain of
membership probabilities, P3D probability that the target is a
member of its given cluster using the full data set or PQG the same
probability computed using a data set filtered to remove targets with
suspect Gaia EDR3 data. More, targets with a membership probability
of -1 were excluded from the membership analysis, also, P3D and
PQG values are not reported for Loden 165 since the
maximum-likelihood calculation failed for this cluster, (i.e see
the section 5.1 Selecting potential cluster members).
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History:
From electronic version of the journal
(End) Luc Trabelsi [CDS] 12-Sep-2024