J/AJ/164/54 Gaia structural parameters of 256 open clusters (Zhong+, 2022)
New Insights into the Structure of Open Clusters in the Gaia Era.
Zhong J., Chen Li, Jiang Y., Qin S., Hou J.
<Astron. J., 164, 54 (2022)>
=2022AJ....164...54Z 2022AJ....164...54Z
ADC_Keywords: Clusters, open; Parallaxes, trigonometric; Proper motions
Keywords: Open star clusters
Abstract:
With the help of Gaia data, it is noted that in addition to the core
components, there are low-density outer halo components in the
extended region of open clusters. In order to study the extended
structure beyond the core radius of the cluster (∼10pc), based on Gaia
Early Data Release 3, taking up to 50pc as the searching radius, we
use the pyUPMASK algorithm to redetermine the member stars of the open
cluster within 1-2kpc. We obtain the member stars of 256 open
clusters, especially those located in the outer halo region of open
clusters. Furthermore, we find that the radial density profile in the
outer region for most open clusters deviates from the Kings profile.
In order to better describe the internal and external structural
characteristics of open clusters, we propose a two-component model: a
core component with a King model distribution and an outer halo
component with a logarithmic Gaussian distribution, and then suggest
using four radii (rc, rt, ro, re) for describing the structure and
distribution profile of star clusters, where rt and re represent the
boundaries of the core component and outer halo component,
respectively. Finally, we provide a catalog of 256 clusters with
structural parameters. In addition, our study shows the sizes of these
radii are statistically linearly related, which indicates that the
inner and outer regions of the cluster are interrelated and follow
similar evolutionary processes. Further, we show that the structure of
two components can be used to better trace the cluster evolution
properties at different stages.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 151 256 Open cluster catalog with structural parameters
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See also:
B/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2015)
J/A+A/543/A156 : Milky Way global survey of star clusters (Kharchenko+, 2012)
J/A+A/558/A53 : Milky Way global survey star clusters. II. (Kharchenko+, 2013)
J/AJ/145/37 : UBVI and Hα CCD photometry of NGC 6231 (Sung+, 2013)
J/A+A/584/A91 : Catalog of dense cores Aquila from Herschel (Konyves+, 2015)
J/MNRAS/456/3757 : Open-cluster density profiles (Seleznev, 2016)
J/A+A/618/A93 : Gaia DR2 open clusters in the Milky Way (Cantat-Gaudin+, 2018)
J/A+A/624/A126 : New open clusters in Perseus direction (Cantat-Gaudin+, 2019)
J/A+A/627/A119 : Extended halo of NGC 2682 (M 67) (Carrera+ 2019)
J/A+A/621/L3 : Hyades tidal tails with Gaia DR2 (Meingast+, 2019)
J/A+A/627/A4 : Praesepe (NGC 2632) and its tidal tails (Roeser+, 2019)
J/A+A/621/L2 : Hyades tidal tails revealed by Gaia DR2 (Roeser+, 2019)
J/A+A/640/A1 : Portrait Galactic disc (Cantat-Gaudin+, 2020)
J/ApJ/889/99 : Gaia DR2 Blanco 1 member candidates (Zhang+, 2020)
J/A+A/645/A84 : Coronae of nearby star clusters (Meingast+, 2021)
J/other/ApSS/366.92 : Stars in Alessi-Teutsch 9 (ASCC 10) (Sanchez+, 2021)
J/A+A/659/A59 : Structural parameters 389 local open clusters (Tarricq+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Cluster Cluster name in CG20 (1)
18- 24 F7.3 deg RAdeg [0.5/354] Mean right ascension of members in
CG20, (ICRS) at Ep=2015.5 (1)
26- 32 F7.3 deg DEdeg [-71/86] Mean declination of members in CG20,
(ICRS) at Ep=2015.5 (1)
34- 40 F7.3 mas/yr pmRA [-11.4/7.68] Mean proper motion along RA of
members in CG20, pmRA*cosDE (1)
42- 47 F6.3 mas/yr pmDE [-9.74/12] Mean proper motion along DE of
members in CG20 (1)
49- 52 F4.2 mas plx [0.44/1.06] Mean parallax members in CG20 (1)
54- 57 I4 pc Dist [1003/1992] Most likely distance of clusters in
CG20 (1)
59- 62 F4.2 [yr] Age [7.0/9.85] Estimated cluster age in CG20 (1)
64- 68 F5.3 --- KDE [0.271/0.589] Bandwidth of kernel density
estimation
70- 74 F5.3 deg Angh [0.03/2.31] Angular size of half number radius
76- 80 F5.3 deg Angc [0.06/2.3] Angular size of King's core radius
derived by the core members
82- 86 F5.3 deg e_Angc [0.001/3] Measurement uncertainty of Angc
88- 92 F5.3 deg Angt [0.11/6.9] Angular size of King's tidal radius
derived by the core members
94- 98 F5.3 deg e_Angt [0.003/9] Measurement uncertainty of Angt
100-104 F5.3 deg Ango [0.09/2.63]? Angular size of mean radius of
outer halo members
106-110 F5.3 deg e_Ango [0/0.13]? Measurement uncertainty of Ango
112-116 F5.3 deg Ange [0.19/7.43]? Angular size of boundary radius of
outer halo members
118-122 F5.3 deg e_Ange [0.003/2]? Measurement uncertainty of Ange
124-127 F4.1 pc Radh [1.3/58] Physical size of half number radius
129-132 F4.1 pc Radc [2.1/54.5] Physical size of King's core radius
derived by the core members
134-138 F5.1 pc Radt [3.6/214] Physical size of King's tidal radius
derived by the core members
140-143 F4.1 pc Rado [2.8/61.2]? Physical size of mean radius of
outer halo members
145-149 F5.1 pc Rade [6.3/149]? Physical size of boundary radius of
outer halo members
151-151 A1 --- Flag Label of cluster samples (2)
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Note (1): CG20 = Cantat-Gaudin+, 2020, J/A+A/640/A1
Note (2): Flags as follows:
C = Present single-component properties that can be approximately
fitted by the King model (27 occurrences)
H = Present the properties of the two components in their RDP fitting
(229 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 25-Oct-2022