J/MNRAS/539/265 Age calibration from star clusters (Ferreira+, 2025)
Open cluster age calibration from colour-magnitude morphological indices using
Gaia DR3 data.
Ferreira F.A., Santos J.F.C.Jr, Corradi W.J.B., Angelo M.S., Maia F.F.S.
<Mon. Not. R. Astron. Soc. 539, 265-281 (2025)>
=2025MNRAS.539..265F 2025MNRAS.539..265F (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Clusters, open ; Photometry ; Optical ; Infrared
Keywords: Hertzsprung-Russell and colour-magnitude diagrams -
stars: horizontal branch - open clusters and associations: general -
galaxies: stellar content
Abstract:
Star clusters are crucial for understanding how stars evolve. Their
colour- magnitude diagrams show the effects of stellar evolution of
approximately coeval objects with the same chemical composition.
Furthermore, the determination of their astrophysical parameters (age,
distance, colour excess and metallicity) together with their spatial
distribution provides information about the structure and the
evolution of the Galaxy itself. Using data from the Gaia DR3 and 2MASS
catalogues, we develop methodologies for characterizing open clusters.
Precise membership lists, mean astrometric parameters and radii are
obtained. Using photometric data from both data sources, we carried
out new age calibrations that rely on morphological indices based on
colour ({DELTA}B-R) and magnitude ({DELTA}G) differences between the
red clump and the turnoff for a sample of 34 open clusters with ages
covering the interval 8.3<log[t(yr)]<9.9. A set of age calibration
functions based on Gaia morphological age indices are determined for
the first time. We demonstrate their accuracy, obtaining a mean
residual of 0.06 dex in log[t(yr)]. Our results also show that stellar
evolution models tend to predict the difference {DELTA}G. However,
they typically overestimate the difference {DELTA}BR for objects
younger than log[t(yr)]=8.8.
Description:
First table (param.dat): informations of the Tables 2 ,4 and A1 from
the paper. This table will provide the OCs astrophysical parameters
from the literature and astrometric parameters obtained in this work.
We also provide the parameters obtained through the CMDs.
Second table (members.dat): memberlists of the OCs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
param.dat 654 34 OCS astrometric astrophysical parameters
RCs and TO
members.dat 141 33126 Member lists of the OCs
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: param.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- ClusterID Internal cluster ID (clu_id)
4- 16 A13 --- Cluster Cluster name (CLUSTER)
18- 27 F10.6 deg RAdeg Cluster center right ascension (ICRS)
at Ep=2016.0 (RA)
29- 39 F11.7 deg DEdeg Cluster center declination (ICRS)
at Ep=2016.0 (DEC)
41- 50 F10.6 deg GLON Cluster center Galactic longitude (L)
52- 63 F12.8 deg GLAT Cluster center Galactic latitude (B)
65- 73 F9.6 arcmin Rlim Limiting Radius in arcmin (RLIM)
75- 85 F11.9 --- R50 Radius in which half of the identified
members are located (R50)
87- 98 F12.8 mas/yr pmRA Cluster proper motion along RA,
pmRA*cosDE (PMRA)
100-111 F12.10 mas/yr e_pmRA Standard error on pmRA (E_PMRA)
113-123 F11.9 mas/yr s_pmRA Standard deviation on pmRA (S_PMRA)
125-136 F12.8 mas/yr pmDE Cluster proper motion along DE (PMDE)
138-149 F12.10 mas/yr e_pmDE Standard error on pmDE (E_PMDE)
151-161 F11.9 mas/yr s_pmDE Standard deviation on pmDE (S_PMDE)
163-172 F10.8 mas plx Cluster mean parallax (PLX)
174-188 E15.7 mas e_plx Standard error on plx (E_PLX)
190-200 F11.9 mas s_plx Standard deviation on plx (S_PLX)
202-205 I4 --- N Number of cluster stars (N)
207-215 F9.6 mag GmagC Apparent magnitude G of the RC (G_CLUMP)
217-236 F20.18 mag e_GmagC Error of the apparent magnitude G of the RC
(EGCLUMP)
238-246 F9.7 mag B-RC Apparent colour Gbp-Grp of the RC (BR_CLUMP)
248-268 F21.19 mag e_B-RC Error of the apparent colour Gbp-Grp of
the RC (EBRCLUMP)
270-279 F10.7 mag GmagTO Apparent magnitude G of the turnoff
(G_CLUMP) (G_TO)
281-291 F11.9 mag e_GmagTO Error of the apparent magnitude G of the
turnoff (EGTO)
293-302 F10.8 mag B-RTO Apparent colour Gbp-Grp of the turnoff
(BR_TO)
304-315 F12.10 mag e_B-RTO Error of the apparent colour Gbp-Grp of the
turn-off (EBRTO)
317-326 F10.8 mag dGmag Difference in magnitude G between the
RC and the turnoff (DELTA_G)
328-346 F19.17 mag e_dGmag Error of the difference in magnitude G
between the RC and the turnoff (EDELTAG)
348-357 F10.8 mag dB_R Difference in colour Gbp-Grp between the
RC and the turnoff (DELTA_BR)
359-378 F20.18 mag edBR Error of the difference in colour Gbp-Grp
between the RC and the turnoff (EDELTABR)
380-389 F10.7 mag KmagC Apparent magnitude K of the RC (K_CLUMP)
391-410 F20.18 mag e_KmagC Error of the apparent magnitude K of the
RC (Expression: $41) (ekclump)
412-421 F10.8 mag J-KC Apparent colour J-K of the RC (JK_CLUMP)
423-433 F11.9 mag e_J-KC Error of the apparent colour J-K of the RC
(EJKCLUMP)
435-440 F6.3 mag KmagTO Apparent magnitude K of the turnoff (K_TO)
442-452 F11.9 mag e_KmagTO Error of the apparent magnitude K of the
turnoff (EKTO)
454-465 F12.9 mag J-KTO Apparent colour J-K of the turnoff (JK_TO)
467-478 F12.10 mag e_J-KTO Error of the apparent colour J-K of the
turnoff (EJKTO)
480-488 F9.7 mag dKmag Difference in magnitude K between the
RC and the turnoff (DELTA_K)
490-508 F19.17 mag e_dKmag Error of the difference in magnitude G
between the RC and the turnoff (EDELTAK)
510-519 F10.8 mag dJ-K Difference in colour J-K between the
RC and the turnoff (DELTA_JK)
521-531 F11.9 mag e_dJ-K Error of the difference in colour J-K
between the RC and the turnoff (EDELTAJK)
533-537 F5.1 --- NClumpG Number of stars in the RC for Gaia
photometry (NCLUMPG)
539-543 F5.1 --- NClumpK Number of stars in the RC for 2MASS
photometry (NCLUMPK)
545-549 F5.2 --- [Fe/H] Metallicity according to N2016 (FeH1)
551-554 F4.2 --- e_[Fe/H] Uncertainty on [Fe/H] according to
N2016 (eFeH)
556-572 F17.15 [yr] logt Age according to N2016 (logt)
574-593 F20.18 [yr] e_logt Uncertainty on Age according to
N2016 (e_logt)
595-598 I4 pc DistDias Cluster distance according to Dias et al.,
2021MNRAS.504..356D 2021MNRAS.504..356D, Cat. J/MNRAS/504/356
(Dist_dias)
600-602 I3 pc e_DistDias rms uncertainty on distance according to
Dias et al., 2021MNRAS.504..356D 2021MNRAS.504..356D,
Cat. J/MNRAS/504/356 (eDistdias)
604-621 F18.15 --- moddist Distance modulus according to Dias et al.,
2021MNRAS.504..356D 2021MNRAS.504..356D, Cat. J/MNRAS/504/356
(moddist)
623-642 F20.18 --- e_moddist rms uncertainty on distance modulus
according to Dias et al.,
2021MNRAS.504..356D 2021MNRAS.504..356D, Cat. J/MNRAS/504/356
(e_moddist)
644-648 F5.3 mag AV Absorption in V band according to Dias et
al., 2021MNRAS.504..356D 2021MNRAS.504..356D,
Cat. J/MNRAS/504/356 (Av)
650-654 F5.3 mag e_AV rms uncertainty on Av according to Dias et
al., 2021MNRAS.504..356D 2021MNRAS.504..356D,
Cat. J/MNRAS/504/356 (e_Av)
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Byte-by-byte Description of file: members.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- ClusterID internal cluster ID (clu_id)
4- 15 A12 --- Name Cluster name (name)
17- 26 F10.6 deg RAdeg right ascension (ICRS) at Ep=2016.0 (RA)
28- 36 F9.5 deg DEdeg Declination (ICRS) at Ep=2016.0 (DEC)
38- 47 F10.6 mas/yr pmRA Proper motion in right ascension direction,
pmRA*cosDE (PMRA)
49- 56 F8.6 mas/yr e_pmRA Standard error of proper motion in right
ascension direction (E_PMRA)
58- 67 F10.6 mas/yr pmDE Proper motion in declination direction
(PMDE)
69- 76 F8.6 mas/yr e_pmDE Standard error of proper motion in
declination direction (E_PMDE)
78- 85 F8.6 mas plx Parallax (PLX)
87- 94 F8.6 mas e_plx Standard error of parallax (E_PLX)
96-103 F8.5 mag BPmag Integrated BP mean magnitude (BPMAG)
105-112 F8.5 mag RPmag Integrated RP mean magnitude (RPMAG)
114-121 F8.5 mag Gmag G-band mean magnitude (GMAG)
123-141 I19 mag GaiaDR3 Gaia DR3 source_id (SOURCE)
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Acknowledgements:
Filipe Andrea Ferreira, filipeandradeferreira(at)hotmail.com
(End) Patricia Vannier [CDS] 28-Mar-2025