J/AJ/170/320 Astrometry & phot. of Gaia DR3 open cluster Cepheids (Deng+, 2025)
Gaia DR3 open cluster Cepheids: A unified catalog with calibrated period-age and
period-Wesenheit relations.
Deng S., He Z., Ren A., Cui Q., Zhou X., Peng L., Wang C., Chen Z.,
Luo Y., Wang K.
<Astron. J., 170, 320 (2025)>
=2025AJ....170..320D 2025AJ....170..320D
ADC_Keywords: Clusters, open; Stars, variable; Isochrones; Proper motions;
Parallaxes, trigonometric; Photometry; Optical; Stars, ages;
Positional data
Keywords: Cepheid variable stars ; Open star clusters ; Astronomy data analysis
Abstract:
Classical Cepheids (CCs) in Galactic open clusters (OCs) provide
essential observational constraints for calibrating the period-age
relation (PAR) and the period-Wesenheit relation (PWR) of CCs.
However, distant and long-period OC Cepheids remain limited, while the
confirmed samples still require more precise determinations of their
physical properties, such as ages and extinctions. In this work, we
present a comprehensive census of OC Cepheids based on an extensive
sample of distant OCs from Gaia Data Release 3 (DR3). By combining
astrometric and photometric membership analyses, we identified 110 CCs
associated with 102 OCs, of which 41 CCs across 37 OCs were classified
as OC Cepheids, while the remaining cases were considered candidate or
rejected associations. Our results are consistent with previous studies,
while 4 of the 41 OC Cepheids are newly reported here. Using updated
cluster parameters derived from manual isochrone fitting, we primarily
refined the PAR to log(Age)=(-0.595±0.044)log(P)+(8.430±0.042) and
recalibrated the PWR to WG=(-3.615±0.083)log(P)+(-2.379±0.096).
This study expands the sample of confirmed and candidate OC Cepheids.
The newly longest-period confirmed OC Cepheid is BM Per (CWNU 3123)
with log(P)=1.36, and two newly confirmed longest-period OC Cepheid
candidates have distances exceeding 6kpc. Moreover, the PAR and PWR
are improved by incorporating refined OC ages and updated parallaxes,
respectively.
Description:
The Classical Cepheid sample used in this study is compiled from six
catalogs published since 2019, including those by
Skowron+2019 (J/AcA/69/305), Chen+2019 (J/other/NatAs/3.320),
Chen+2020 (J/ApJS/249/18), Pietrukowicz+2021 (2021AcA....71..205P 2021AcA....71..205P),
Inno+2021 (J/ApJ/914/127), and Ripepi+2022 (J/A+A/659/A167).
The open cluster (OC) data used in this study, collected from the Gaia
astrometric mission (Gaia DR3, I/355), provide stellar positions and
proper motions along with photometry in the Gaia bands (G, BP, RP).
Our OC sample is compiled from the catalogs of He+2022 (J/ApJS/260/8,
hereafter He22), He+2023 (J/ApJS/264/8, hereafter He23), and Hunt+2024
(J/A+A/686/A42, hereafter HR24). We also supplemented our sample with
additional OCs from Cantat-Gaudin+2020 (J/A+A/640/A1, hereafter CG20)
and Cruz Reyes+2023 (J/A+A/672/A85, hereafter CRA23), incorporating
three OCs from each catalog.
By compiling Galactic OC Cepheids from five studies, including
Zhou+2021MNRAS.504.4768Z, Hao+2022 (J/A+A/668/A13),
Lin+2022ApJ...938...33L, CRA23, and Wang+2024AJ....168...34W, we
obtained a total of 66 CCs associated with 59 OCs. Additionally, we
took into account the OC Cepheid candidates reported by
Majaess+2024PASP..136i4202M.
After applying our selection criteria, the final sample consists of
110 CCs associated with 102 OCs. We classified the 110 OC-Cepheid
pairs, comprising 110 CCs associated with 102 OCs, into three categories:
reliable OC Cepheids, OC Cepheid candidates, and rejected samples.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 127 110 Astrometric parameters of the 41 open cluster
Cepheids, 19 Cepheid candidates, and 50 rejected
sources
table2.dat 110 110 Pulsation mode, period, Gaia-band magnitudes, and
metallicity of 41 open cluster Cepheids, 19 open
cluster Cepheid candidates, and 50 rejected
sources
table3.dat 52 110 Recalibrated parallax, extinction, distance
modulus, and age of open clusters from isochrone
fitting
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
II/366 : ASAS-SN catalog of variable stars (Jayasinghe+, 2018-2020)
III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)
J/A+A/498/949 : Veloc. of 1253 F-K dwarfs in open clusters (Mermilliod+, 2009)
J/ApJ/722/605 : A stellar rotation census of B stars (Huang+, 2010)
J/A+A/537/A120 : Rotational velocities of A-type stars. IV. (Zorec+, 2012)
J/MNRAS/434/2238 : Cepheids in open clusters (Anderson+, 2013)
J/ApJ/842/42 : Improved reddenings for 59 Galactic Cepheids (Madore+, 2017)
J/AcA/67/297 : OGLE Galactic center Cepheids and RR Lyrae (Soszynski+, 2017)
J/ApJS/237/28 : WISE catalog of periodic variable stars (Chen+, 2018)
J/AJ/156/241 : A first cat. of variable stars measured by ATLAS (Heinze+, 2018)
J/AcA/68/315 : OGLE Galactic Cepheids (Udalski+, 2018)
J/other/NatAs/3.320 : Galactic classical Cepheids catalog (Chen+, 2019)
J/ApJ/876/85 : HST observations for LMC Cepheids (Riess+, 2019)
J/A+A/625/A14 : Reclassification of Cepheids in the Gaia DR2 (Ripepi+, 2019)
J/AcA/69/305 : Northern Galactic disk classical Cepheids (Skowron+, 2019)
J/A+A/640/A1 : Portrait Galactic disc (Cantat-Gaudin+, 2020)
J/ApJS/249/18 : The ZTF catalog of periodic variable stars (Chen+, 2020)
J/MNRAS/504/356 : Updated parameters of 1743 open clusters (Dias+, 2021)
J/ApJ/914/127 : Gaia-ASAS-SN classical Cepheid sample. I. (Inno+, 2021)
J/A+A/649/A3 : Gaia Early Data Release 3 photometric passbands (Riello+, 2021)
J/MNRAS/505/5978 : Gaia EDR3 view on Gal. globular clusters (Vasiliev+, 2021)
J/A+A/661/A118 : 628 new open clusters with OCfinder (Castro-Ginard+, 2022)
J/A+A/668/A13 : Open clusters housing classical Cepheids (Hao+, 2022)
J/ApJS/260/8 : 541 new open cluster candidates (He+, 2022)
J/A+A/659/A167 : Cepheid Period-Wesenheit-Metallicity relation (Ripepi+, 2022)
J/A+A/672/A85 : Galactic Cepheid luminosity scale (Cruz Reyes+, 2023)
J/ApJS/264/8 : 1656 new CWNU star clusters (He+, 2023)
J/A+A/676/A129 : Gaia-ESO catalogue version 5.1 (Hourihane+, 2023)
J/A+A/674/A17 : Gaia Data Release 3. The Cepheids sample (Ripepi+, 2023)
J/A+A/686/A42 : Improving the open cluster census. III. (Hunt+, 2024)
J/A+A/690/A284 : VELOCE II. spectroscopic binary Cepheids (Shetye+, 2024)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Index [1/110] Internal index number (1)
5- 32 A28 --- Name Identifier
34- 40 F7.3 deg RAdeg Right Ascension (J2000)
42- 48 F7.3 deg DEdeg Declination (J2000)
50- 54 F5.3 mas plx [0.091/2.2] Parallax with zero-point
correction
56- 60 F5.3 mas e_plx [0.028/0.08] Uncertainty in plx
62- 66 F5.2 mas/yr pmRA [-7.99/3.1] Proper motion along RA
68- 71 F4.2 mas/yr e_pmRA [0.02/0.07] Uncertainty in pmRA
73- 77 F5.2 mas/yr pmDE [-8.14/4.92] Proper motion along DE
79- 82 F4.2 mas/yr e_pmDE [0.02/0.08] Uncertainty in pmDE
84- 87 F4.2 --- dplx [0.01/5.47] Astrometric dispersion in
parallax (deltaplx) (2)
89- 93 F5.2 --- dpm [0.14/25.79] Astrometric dispersion in proper
motion (deltapm) (2)
95- 99 F5.2 --- R [0.08/49.86] Angular distance of classical
Cepheid from cluster center
101- 113 A13 --- Note Source note (3)
115- 127 A13 --- Cluster Cluster identifier
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Note (1): Sources 1-41 are known open cluster Cepheids.
Sources 42-60 are open cluster Cepheid candidates.
Sources 61-110 are rejected samples.
Note (2): These denote the deviations of Cepheids from their host
open clusters in parallax and proper motion.
Note (3): Note as follows:
Y = Newly identified open cluster Cepheid; 27 occurrences
N = Previously identified open cluster Cepheid; 83 occurrences
1 = Zhou+2021 (2021MNRAS.504.4768Z 2021MNRAS.504.4768Z); 36 occurrences
2 = Hao+2022 (J/A+A/668/A13); 42 occurrences
3 = Lin+2022 (2022ApJ...938...33L 2022ApJ...938...33L); 47 occurrences
4 = Cruz Reyes+2023 (J/A+A/672/A85); 32 occurrences
5 = Wang+2024 (2024AJ....168...34W 2024AJ....168...34W); 41 occurrences
6 = Majaess+2024 (2024PASP..136i4202M 2024PASP..136i4202M); 31 occurrences
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Index [1/110] Internal index number (1)
5- 32 A28 --- Name Identifier
34 A1 --- f_Name =* Indicates Gaia DR3 (I/355) photometry was
adopted
36- 63 A28 --- GaiaDR3 Gaia DR3 (I/355) identifier
65- 68 A4 --- Mode Pulsation mode (5)
70- 74 F5.2 d Per [0.29/44.99] Period
76- 80 F5.2 mag Gmag [5.74/17.48] Gaia G passband
intensity-averaged magnitude (2)
82- 86 F5.2 mag BPmag [6.14/18.19] Gaia Blue passband
intensity-averaged magnitude (2)
88- 92 F5.2 mag RPmag [5.14/16.63] Gaia Red passband
intensity-averaged magnitude (2)
94- 98 F5.2 [-] [M/H] [-0.18/0.52]? Metallicity of classical
Cepheids (3)
100- 110 A11 --- Ref Reference code for the Classical Cepheid (4)
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Note (1): Sources 1-41 are known open cluster Cepheids.
Sources 42-60 are open cluster Cepheid candidates.
Sources 61-110 are rejected samples.
Note (2): For Classical Cepheids' photometry, the intensity-averaged magnitudes
were extracted from gaiadr3.vari_cepheid (Ripepi+2023, J/A+A/674/A17).
In other cases, see the "f_Name" column, Gaia DR3 (I/355) photometry
was adopted.
Note (3): Taken from the Classical Cepheid catalog of
Ripepi+2022 (J/A+A/659/A167).
Note (4): References as follows:
a = Skowron+2019 (2019AcA...517...69S 2019AcA...517...69S); 73 occurrences
b = Chen+2019 (J/other/NatAs/3.320); 31 occurrences
c = Chen+2020 (J/ApJS/249/18); 89 occurrences
d = Inno+2021 (J/ApJ/914/127); 59 occurrences
e = Pietrukowicz+2021 (2021AcA....71..205P 2021AcA....71..205P); 97 occurrences
f = Ripepi+2022 (J/A+A/659/A167); 32 occurrences
g = ? ; 2 occurrences
Note (5): Pulsation mode as follows:
F = Fundamental mode pulsator (75 occurrences)
1O = First overtone mode pulsator (30 occurrences)
F10 = Fundamental and first overtone modes pulsator (4 occurrences)
1O2O = First and second overtone modes pulsator (1 occurrence)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Index [1/110] Internal index number (1)
5- 17 A13 --- Cluster Cluster identifier (Name)
19- 23 F5.3 mas plx [0.095/2.311] Parallax
25- 29 F5.3 mas e_plx [0.002/0.025] Uncertainty in plx
31- 34 F4.2 mag Av [0.05/6.58] V-band extinction
36- 40 F5.2 mag DM [8.18/15.11] Distance modulus
42- 45 F4.2 [yr] logA [7.0/9.15] Log of age
47- 50 F4.2 [yr] e_logA [0.03/0.15] Uncertainty in logA
52 A1 --- Ref Reference code for the open cluster (2)
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Note (1): Sources 1-41 are known open cluster Cepheids.
Sources 42-60 are open cluster Cepheid candidates.
Sources 61-110 are rejected samples.
Note (2): Reference as follows:
A = He+2023 (2023ApJS..264....8H 2023ApJS..264....8H); 18 occurrences
B = Hunt+2024 (J/A+A/686/A42); 79 occurrences
C = He+2022 (2022ApJS..260....8H 2022ApJS..260....8H); 7 occurrences
D = Cantat-Gaudin+2020 (J/A+A/640/A1); 3 occurrences
E = Cruz Reyes+2023 (J/A+A/672/A85) ; 3 occurrences
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History:
From electronic version of the journal
License: CC-BY-4.0
(End) Prepared by [AAS], Robin Leichtnam [CDS] 27-Aug-2026