J/ApJ/912/162 Open clusters in solar neighborhood (Pang+, 2021)
3D morphology of open clusters in the solar neighborhood with Gaia EDR 3:
its relation to cluster dynamics.
Pang X., Li Y., Yu Z., Tang S.-Y., Dinnbier F., Kroupa P., Pasquato M.,
Kouwenhoven M.B.
<Astrophys. J. 912, 162 (2021)>
=2021ApJ...912..162P 2021ApJ...912..162P (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Clusters, open ; Stars, nearby ; Stars, distances
Keywords: stars: evolution - open clusters and associations: individual -
stars: kinematics and dynamics - methods: statistical -
methods: numerical
Abstract:
We analyze the 3D morphology and kinematics of 13 open clusters (OCs)
located within 500pc of the Sun, using Gaia EDR3 and kinematic data
from literature. Members of OCs are identified using the unsupervised
machine learning method StarGO, using 5D parameters (X, Y, Z,
µ_αcosδ, µ_δ). The OC sample covers an age
range of 25Myr-2.65Gyr. We correct the asymmetric distance
distribution due to the parallax error using Bayesian inversion. The
uncertainty in the corrected distance for a cluster at 500pc is
3.0-6.3pc, depending on the intrinsic spatial distribution of its
members. We determine the 3D morphology of the OCs in our sample and
fit the spatial distribution of stars within the tidal radius in each
cluster with an ellipsoid model. The shapes of the OCs are
well-described with oblate spheroids (NGC 2547, NGC 2516, NGC 2451A,
NGC 2451B, NGC 2232), prolate spheroids (IC 2602, IC 4665, NGC 2422,
Blanco 1, Coma Berenices), or triaxial ellipsoids (IC 2391, NGC 6633,
NGC 6774). The semi-major axis of the fitted ellipsoid is parallel to
the Galactic plane for most clusters. Elongated filament-like
substructures are detected in three young clusters (NGC 2232,
NGC 2547, NGC 2451B), while tidal-tail-like substructures (tidal
tails) are found in older clusters (NGC 2516, NGC 6633, NGC 6774,
Blanco 1, Coma Berenices). Most clusters may be super-virial and
expanding. N-body models of rapid gas expulsion with an SFE of ∼1/3
are consistent with clusters more massive than 250M☉, while
clusters less massive than 250M☉ tend to agree with adiabatic
gas expulsion models. Only six OCs (NGC 2422, NGC 6633, and NGC 6774,
NGC 2232, Blanco 1, Coma Berenices) show clear signs of mass
segregation.
Description:
Corrected 3D positions of members in all target clusters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 92 13 General parameters of target clusters
table2.dat 259 6608 Corrected 3D positions of members in all target
clusters
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Cluster Cluster identifier
16- 19 I4 Myr Age Age (when the referenced age fits the members,
we adopt the age from previous works)
20 A1 --- r_Age Age reference (1)
22- 26 F5.1 pc Distcor Mean corrected distance of members
28- 30 F3.1 pc e_Distcor Error in corrected distance following the
Bayesian model described in Section 4.1
32- 34 F3.1 --- rh Half-mass radius
36- 39 F4.1 --- rt Tidal radius
41- 46 F6.1 Msun Mcl Cluster mass
48- 53 F6.1 Msun Mdyn Dynamical mass
55- 59 F5.3 --- Z Metallicity
60 A1 -- r_Z Z reference (1)
62- 65 F4.2 mag E(B-V) Reddening E(B-V)
66 A1 --- r_E(B-V) E(B-V) reference (1)
68- 71 I4 --- Members Number of members
73- 75 I3 --- CG18 Number of matched members in Cantat-Gaudin et
al. (2018A&A...618A..93C 2018A&A...618A..93C, Cat. J/A+A/618/A93)
77- 81 A5 --- CG18% Percentage of matched members in
Cantat-Gaudin et al. (2018A&A...618A..93C 2018A&A...618A..93C,
Cat. J/A+A/618/A93)
83- 86 I4 --- LP19 ?=- Number of matched members in Liu & Pang
(2019ApJS..245...32L 2019ApJS..245...32L, Cat. J/ApJS/245/32)
88- 92 A5 --- LP19% Percentage of matched members in Liu & Pang
(2019ApJS..245...32L 2019ApJS..245...32L, Cat. J/ApJS/245/32)
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Note (1): References as follows:
a = Marsden et al. (2009MNRAS.399..888M 2009MNRAS.399..888M)
b = Postnikova et al. (2020RAA....20...16P 2020RAA....20...16P)
c = Miret-Roig et al. (2019A&A...631A..57M 2019A&A...631A..57M, Cat. J/A+A/631/A57)
d = Bailey et al. (2018MNRAS.475.1609B 2018MNRAS.475.1609B, Cat. J/MNRAS/475/1609)
e = Gaia Collaboration et al. (2018A&A...616A...1G 2018A&A...616A...1G, Cat. I/345)
f = Williams & Bolte (2007AJ....133.1490W 2007AJ....133.1490W)
g = Olivares et al. (2019A&A...625A.115O 2019A&A...625A.115O, Cat. J/A+A/625/A115)
h = Balog et al. (2009ApJ...698.1989B 2009ApJ...698.1989B, Cat. J/ApJ/698/1989)
i = Pang et al. (2020ApJ...900L...4P 2020ApJ...900L...4P)
j = Zhang et al. (2020ApJ...889...99Z 2020ApJ...889...99Z, Cat. J/ApJ/889/99)
k = Tang et al. (2019ApJ...877...12T 2019ApJ...877...12T, Cat. J/ApJ/877/12)
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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 --- Cluster Cluster identifier
16- 34 I19 --- GaiaEDR3 Gaia EDR3 object identifier
36- 50 F15.11 deg RAdeg Gaia EDR3 right ascension (ICRS) at Ep=J2016.0
52- 57 F6.4 mas e_RAdeg Uncertainty in RAdeg
59- 73 F15.11 deg DEdeg Gaia EDR3 Declination (ICRS) at Ep=2016.0
75- 80 F6.4 mas e_DEdeg Uncertainty in DEdeg
82- 88 F7.4 mas plx Gaia EDR3 parallax
90- 95 F6.4 mas e_plx Uncertainty in plx
97-103 F7.3 mas/yr pmRA Gaia EDR3 proper motion along RA*cosDE
105-109 F5.3 mas/yr e_pmRA Uncertainty in pmRA
111-117 F7.3 mas/yr pmDE Gaia EDR3 proper motion along DE
119-123 F5.3 mas/yr e_pmDE Uncertainty in pmDE
125-133 F9.6 mag Gmag Apparent Gaia EDR3 G band magnitude
135-143 F9.6 mag BPmag Apparent Gaia EDR3 blue band magnitude
145-153 F9.6 mag RPmag Apparent Gaia EDR3 red band magnitude
155-162 F8.2 km/s GRV ?=-9999 Gaia EDR3 radial velocity
164-171 F8.2 km/s e_GRV ?=-9999 Uncertainty in GRV
173-180 F8.2 km/s JRV ?=-9999 Gaia/ESO survey (Jackson et al.,
2020MNRAS.496.4701) radial velocity
182-189 F8.2 km/s e_JRV ?=-9999 Uncertainty in JRV
191-198 F8.2 km/s BRV ?=-9999 Bailey et al. (2018,
Cat. J/MNRAS/475/1609) radial velocity
200-207 F8.2 km/s e_BRV ?=-9999 Uncertainty in BRV
209-211 F3.1 Msun Mass Stellar mass from this study
213-218 F6.1 pc Xobs Heliocentric Cartesian X coordinate (1)
220-225 F6.1 pc Yobs Heliocentric Cartesian Y coordinate (1)
227-232 F6.1 pc Zobs Heliocentric Cartesian Z coordinate (1)
234-239 F6.1 pc Xcor Heliocentric Cartesian X coordinate (2)
241-246 F6.1 pc Ycor Heliocentric Cartesian Y coordinate (2)
248-253 F6.1 pc Zcor Heliocentric Cartesian Z coordinate (2)
255-259 F5.1 pc Dist Corrected distance
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Note (1): Computed via direct inverting Gaia EDR 3 parallax.
Note (2): After distance correction in this study.
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Acknowledgements:
Shih-Yun Tang, sytang(at)lowell.edu
References:
Pang et al. Paper II. 2022ApJ...931..156P 2022ApJ...931..156P Cat. J/ApJ/931/156
(End) Patricia Vannier [CDS] 27-May-2021