J/ApJS/264/8 1656 new CWNU star clusters (He+, 2023)
Unveiling hidden stellar aggregates in the Milky Way:
1656 new star clusters found in Gaia EDR3.
He Z., Liu X., Luo Y., Wang K., Jiang Q.
<Astrophys. J. Suppl. Ser., 264, 8 (2023)>
=2023ApJS..264....8H 2023ApJS..264....8H
ADC_Keywords: Surveys ; Clusters, open ; Parallaxes, trigonometric ;
Proper motions ; Radial velocities
Keywords: Galaxy: stellar content - star clusters: general - surveys: Gaia
Abstract:
We report 1,656 new star clusters found in the Galactic disk
(|b|<20deg) beyond 1.2kpc, using Gaia EDR3 data. Based on an
unsupervised machine learning algorithm, DBSCAN, and followed our
previous studies, we utilized a unique method to do the data
preparation and obtained the clustering coefficients, which proved to
be an effective way to search blindly for star clusters. We tabulated
the physical parameters and member stars of the new clusters, and
presented some interesting examples, including a globular cluster
candidate. We examined the new discoveries and discussed their
statistical properties. The proper motion dispersions and radii of the
new clusters were the same as the previously reported ones. The new
star clusters beyond 1.2kpc were older than those in the solar
neighborhood, and the new objects found in the third Galactic quadrant
presented the lowest line-of-sight extinctions. Combined with our
previous results, the total population of new clusters detected
through our method was 2541, corresponding to 55% of all newly
published clusters in the Gaia era. The number of cataloged Gaia star
clusters was also increased to nearly six thousand. In the near
future, it is necessary to make a unified confirmation and member star
determination for all reported clusters.
Description:
clusters.dat contains astrophysical parameters for the 1656 new star
clusters identified in this work.
members.dat contains astrometric and photometric parameters of 48714
member stars from Gaia EDR3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
clusters.dat 110 1656 Parameters for the 1656 objects (table 1)
members.dat 239 48714 Gaia EDR3/DR3 parameters of the member stars
(table 2)
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See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
J/other/RAA/21.93 : 74 new open clusters found in Gaia DR2 (He+, 2021)
J/ApJS/260/8 : 541 new open cluster candidates (He+, 2022)
J/ApJS/262/7 : 886 nearby star clusters (He+, 2022)
Byte-by-byte Description of file: clusters.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- CWNU Cluste identifier in CWNU (CWNU_id)
6- 12 F7.3 deg GLON [] Galactic longitude (l)
14- 20 F7.3 deg GLAT Galactic latitude (b)
22- 26 F5.3 deg s_GLON 1-sigma dispersion in l (sig_l)
28- 32 F5.3 deg s_GLAT 1-sigma dispersion in b (sig_b)
34- 36 I3 --- Num Number of member stars (n)
38- 42 F5.3 mas plx median parallax (plx)
44- 48 F5.3 mas s_plx 1-sigma dispersion in plx (sig_plx)
50- 55 F6.3 mas/yr pmRA Median proper motion along RA, pmRA*cosDE
(pmx)
57- 61 F5.3 mas/yr s_pmRA 1-sigma dispersion in pmx (sig_pmx)
63- 68 F6.3 mas/yr pmDE Median proper motion along DE (pmy)
70- 74 F5.3 mas/yr s_pmDE 1-sigma dispersion in pmy (sig_pmy)
76- 82 F7.2 km/s RV ? Median radial velocity (rv)
84- 88 F5.2 km/s s_RV ? 1-sigma dispersion in rv (sig_rv)
90- 91 I2 --- o_RV Number of member stars with radial velocity
error <5km/s (nrv)
93- 97 F5.2 [yr] logAge logarithmic age (logage) (1)
99-102 F4.2 mag A0 Extinction at 550nm (A0) (1)
104-108 F5.2 mag m-M Distance modulus (m-M) (1)
110 I1 --- Class classification of the new clusters (class)
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Note (1): The typical fitted accuracy for logage A0, and m-M are 0.05 dex,
0.05mag, and 0.05, respectively.
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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- 19 I19 --- GaiaEDR3 Gaia EDR3 identifier (source_id)
21- 40 F20.16 deg GLON Galactic longitude (l)
42- 63 E22.16 deg GLAT Galactic latitude (b)
65- 75 F11.8 --- RUWE Renormalised unit weight error for
astrometry (ruwe)
77- 95 F19.17 mas plx Parallax (parallax)
97-108 F12.10 mas e_plx Uncertainty in parallax (parallax)
110-131 E22.16 mas/yr pmRA proper motion along R.A. (pmra)
133-144 F12.10 mas/yr e_pmRA Uncertainty in pmra (pmra_error)
146-167 E22.15 mas/yr pmDE proper motion along Dec. (pmdec)
169-180 F12.10 mas/yr e_pmDE Uncertainty in pmdec (pmdec_error)
182-195 F14.9 km/s RV ? Gaia DR3 radial velocity (radial_velocity)
197-207 F11.8 km/s e_RV ? Uncertainty in radial_velocity
(radialvelocityerror)
209-218 F10.7 mag Gmag G band magnitude (photgmean_mag)
220-231 F12.9 mag BP-RP BP-RP color (bp_rp)
233-234 I2 --- nre [1/11] Response frequency (nre) (1)
236-239 I4 --- CWNU Cluster identifier in CWNU catalog (cwnu_id)
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Note (1): The NRE value (from 1 to 11) is the number of frequency derived from
DBSCAN.
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Acknowledgements:
Zhihong He, hezh(at)cwnu.edu.cn
References:
Gaia Collaboration, 2021A&A...649A...1G 2021A&A...649A...1G, Gaia EDR3
(End) Patricia Vannier [CDS] 19-Sep-2022