J/ApJ/931/156 3D morphology of open clusters with Gaia EDR3. II. (Pang+, 2022)
3D morphology of open clusters in the solar neighborhood with Gaia EDR3.
II. Hierarchical star formation revealed by spatial and kinematic substructures.
Pang X., Tang S.-Y., Li Y., Yu Z., Wang L., Li J., Li Y., Wang Y.,
Wang Y., Zhang T., Pasquato M., Kouwenhoven M.B.N.
<Astrophys. J., 931, 156 (2022)>
=2022ApJ...931..156P 2022ApJ...931..156P
ADC_Keywords: Clusters, open; Radial velocities; Proper motions; Surveys;
Optical; Stars, masses; Morphology
Keywords: Open star clusters ; Young star clusters ; Stellar kinematics ;
Stellar dynamics ; Astrostatistics
Abstract:
We identify members of 65 open clusters in the solar neighborhood
using the machine-learning algorithm StarGO based on Gaia EDR3 data.
After adding members of 20 clusters from previous studies we obtain
85 clusters, and study their morphology and kinematics. We classify
the substructures outside the tidal radius into four categories:
filamentary (f1) and fractal (f2) for clusters <100Myr, and halo (h)
and tidal tail (t) for clusters >100Myr. The kinematical substructures
of f1-type clusters are elongated; these resemble the disrupted
cluster Group X. Kinematic tails are distinct in t-type clusters,
especially Pleiades. We identify 29 hierarchical groups in four young
regions (Alessi 20, IC 348, LP 2373, LP 2442); 10 among these are new.
The hierarchical groups form filament networks. Two regions (Alessi20,
LP 2373) exhibit global orthogonal expansion (stellar motion
perpendicular to the filament), which might cause complete dispersal.
Infalling-like flows (stellar motion along the filament) are found in
UBC 31 and related hierarchical groups in the IC 348 region. Stellar
groups in the LP 2442 region (LP 2442 gp 1-5) are spatially well mixed
but kinematically coherent. A merging process might be ongoing in the
LP 2442 subgroups. For younger systems (≲30Myr), the mean axis ratio,
cluster mass, and half-mass-radius tend to increase with age values.
These correlations between structural parameters may imply two
dynamical processes occurring in the hierarchical formation scenario
in young stellar groups: (1) filament dissolution and (2) subgroup
mergers.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 102 85 Parameters of 85 open clusters
table2.dat 224 22027 Individual members of the 65 clusters identified
in this work
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See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
J/ApJ/551/852 : FCRAO CO survey of the outer Galaxy (Heyer+, 2001)
J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)
J/ApJ/764/73 : HST VI phot. of HD 97950 cluster members stars (Pang+, 2013)
J/A+A/584/A91 : Cat. of dense cores in Aquila from Herschel (Konyves+, 2015)
J/ApJ/812/131 : Spatial structure of young stellar cl. III. (Kuhn+, 2015)
J/MNRAS/460/2593 : Cygnus OB2 DANCe: Proper motion study (Wright+, 2016)
J/A+A/608/A148 : Stellar populations towards Orion with GaiaDR1 (Zari+, 2017)
J/A+A/616/A10 : 46 open clusters GaiaDR2 HR diagrams (Gaia Col., 2018)
J/A+A/619/A155 : Open cluster kinematics with Gaia DR2 (Soubiran+, 2018)
J/ApJ/862/106 : Stellar & substellar members in Coma Berenices (Tang+, 2018)
J/MNRAS/475/5659 : OB association members (Ward+, 2018)
J/A+A/623/A108 : Age of 269 GDR2 open clusters (Bossini+, 2019)
J/A+A/621/A115 : Vela OB2 members (Cantat-Gaudin+, 2019)
J/A+A/626/A17 : Young pop. in Vela-Puppis region (Cantat-Gaudin+, 2019)
J/A+A/627/A119 : Extended halo of NGC 2682 (M 67) (Carrera+ 2019)
J/AJ/158/122 : Local structure & SFH of the MW (Kounkel+, 2019)
J/ApJ/870/32 : Kinematics in young star clusters & assoc. (Kuhn+, 2019)
J/ApJS/245/32 : Newly identified star clusters in Gaia DR2 (Liu+, 2019)
J/A+A/628/A66 : alpha Persei, Pleiades and Praesepe clusters (Lodieu+, 2019)
J/ApJ/885/131 : High-mass SFR plx & proper motion with VLBI (Reid+, 2019)
J/A+A/627/A4 : Praesepe (NGC 2632) and its tidal tails (Roeser+, 2019)
J/ApJ/877/12 : Coma Ber & Neighbor Stellar Group tidal tails (Tang+, 2019)
J/A+A/643/A12 : Chemical abundances of 6 open cluster stars (Casali+, 2020)
J/A+A/635/A45 : Open clusters in the Galactic disc (Castro-Ginard+, 2020)
J/MNRAS/495/663 : Gaia DR2 OB associations (Ward+, 2020)
J/ApJ/891/39 : LAMOST DR3 very metal-poor stars of Gal. halo (Yuan+, 2020)
J/AJ/162/197 : Phot., rotation & Li in open cluster NCG2516 (Bouma+, 2021)
J/A+A/647/A137 : 800pc tital tail of Hyades (Jerabkova+, 2021)
J/ApJ/917/23 : SPYGLASS. I. Mapping young stellar structures (Kerr+, 2021)
J/ApJ/912/162 : Open clusters in solar neighborhood (Pang+, 2021)
J/ApJ/923/20 : Hierarchical clustering in Vela OB2 complex (Pang+, 2021)
J/A+A/659/A59 : Structural param. of local open clusters (Tarricq+, 2022)
J/A+A/660/A4 : Gaia EDR3 new Galactic open clusters (Hao+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Cl Cluster name
16 A1 --- f_Cl Flag on Cl (1)
18- 27 F10.6 deg RAdeg [1.5/356.1] Right ascension (J2000) (2)
29- 38 F10.6 deg DEdeg [-68.2/69] Declination (J2000) (2)
40- 44 F5.1 pc Dist [85.6/652.5] Distance after correction
in Section 3 (2)
46- 51 F6.2 km/s RV [-29/43] Radial velocity (2)
53- 59 F7.3 mas/yr pmRA [-36/20] Proper motion in right ascension
direction (pmRA*cosDE) (2)
61- 67 F7.3 mas/yr pmDE [-45.4/23.4] Proper motion in declination (2)
69- 72 I4 Myr Age [3/2650] Age derived from PARSEC isochrone
fitting
74- 79 F6.1 Msun Mcl [42/2210.5] Total mass of each star cluster
81- 84 F4.1 pc rh [2.5/22] Half mass radius of the cluster
86- 89 F4.1 pc rt [4.9/18.3] Tidal radius of the cluster
91- 94 I4 --- N [57/2690] Total number of members
96- 99 F4.2 --- fm [0.09/1] Bound mass fraction (ratio of mass
within the tidal radius)
101- 102 A2 --- Flag Morphological flag (3)
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Note (1): Flag as follows:
a = New hierarchical groups identified in this work (10 occurrences).
b = Clusters members taken from Pang+ (2021, J/ApJ/912/162 and
2021, J/ApJ/923/20); Li+ (2021RNAAS...5..173L 2021RNAAS...5..173L).
Note (2): The median value of cluster members.
Note (3): The morphological type of the cluster substructures outside rt
as follows:
f1 = filamentary (19 occurrences)
f2 = fractal (21 occurrences)
h = halo (3 occurrences)
t = tidal tail (10 occurrences)
d = Group X; for its total disruption state (Tang+ 2019, J/ApJ/877/12).
See Section 4.1 for a further description.
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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- 14 A14 --- Cl Cluster name
16- 34 I19 --- Gaia Gaia EDR3 identifier
36- 50 F15.11 deg RAdeg Right Ascension (ICRS) at Ep=2016
52- 57 F6.4 deg e_RAdeg [0.004/0.5] Uncertainty in RAdeg
59- 73 F15.11 deg DEdeg [-73.1/72.2] Declination (ICRS) at Ep=2016
75- 80 F6.4 deg e_DEdeg [0.006/0.3] Uncertainty in DEdeg
82- 88 F7.4 mas plx [1.48/13] Gaia EDR3 parallax
90- 95 F6.4 mas e_plx [0.008/0.5] Uncertainty in plx
97- 103 F7.3 mas/yr pmRA [-40.1/10.5] Gaia EDR3 proper motion along RA
*cos(DE)
105- 109 F5.3 mas/yr e_pmRA [0.007/0.7] Uncertainty in pmRA
111- 117 F7.3 mas/yr pmDE [-26.5/14.1] Gaia EDR3 proper motion along DE
119- 123 F5.3 mas/yr e_pmDE [0.008/0.4] Uncertainty in pmDE
125- 133 F9.6 mag Gmag [4/19.6] Gaia EDR3 G band magnitude
135- 143 F9.6 mag Bpmag [4.6/21.5] Gaia EDR3 Blue passband magnitude
145- 153 F9.6 mag Rpmag [3/19.5] Gaia EDR3 Red passband magnitude
155- 162 F8.2 km/s RVel [/103]?=-9999 Gaia EDR3 radial velocity
164- 171 F8.2 km/s e_RVel [/20]?=-9999 Uncertainty in RVel
173- 176 F4.1 Msun Mass [0.1/13.7] Stellar mass from this study
178- 183 F6.1 pc Xobs [-486/503] Heliocentric X Cartesian coordinate
(1)
185- 190 F6.1 pc Yobs [-568/554] Heliocentric Y Cartesian coordinate
(1)
192- 197 F6.1 pc Zobs [-251/141] Heliocentric Z Cartesian coordinate
(1)
199- 204 F6.1 pc Xcor [-477/486]? Heliocentric X Cartesian
coordinate (2)
206- 211 F6.1 pc Ycor [-554/549]? Heliocentric Y Cartesian
coordinate (2)
213- 218 F6.1 pc Zcor [-249/141]? Heliocentric Z Cartesian
coordinate (2)
220- 224 F5.1 pc DCor [109/662]? Corrected distance
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Note (1): Computed via direct inverting Gaia EDR3 parallax.
Note (2): After distance correction in this study.
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History:
From electronic version of the journal
References:
Pang et al. Paper I. 2021ApJ...912..162P 2021ApJ...912..162P Cat. J/ApJ/912/162
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 10-Apr-2024