J/A+A/686/A225 Star cluster systems Collinder 135 and UBC 7 (Ishchenko+, 2024)
Star-by-star dynamical evolution of the physical pair of the Collinder 135 and
UBC 7 open clusters.
Ishchenko M., Kovaleva D.A., Berczik P., Kharchenko N.V., Piskunov A.E.,
Polyachenko E., Postnikova E., Just A., Borodina O., Omarov C., Sobodar O.
<Astron. Astrophys. 686, A225 (2024)>
=2024A&A...686A.225I 2024A&A...686A.225I (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stellar distribution ; Proper motions ;
Parallaxes, trigonometric ; Photometry ; Optical
Keywords: open clusters and associations: individual -
open clusters and associations: individual: Collinder 135 -
open clusters and associations: individual: UBC 7 - methods: numerical
Abstract:
In a previous paper using Gaia DR2 data, we demonstrated that the two
closely situated open clusters Collinder 135 and UBC 7 might have
formed together about 50Myr ago.
In this work, we performed star-by-star dynamical modelling of the
evolution of the open clusters Collinder 135 and UBC 7 from their
supposed initial state to their present-day state, reproducing
observational distributions of members.
Modelling of the Collinder 135 and UBC 7 dynamical evolution was done
using the high-order parallel N-body code phi-GPU with up-to-date
stellar evolution. Membership and characteristics of the clusters were
acquired based on Gaia DR3 data.
The comparison of the present-day radial cumulative star count
obtained from the N-body simulations with the current observational
data gave us full consistency of the model with observational data,
especially in the central 8 pc, where 80% of the stars reside. The
proper motion velocity components obtained from the N-body simulations
of the stars are also quite consistent with the observed distributions
and error bars.
These results show that our numerical modelling is able to reproduce
the open clusters' current complex 6D observed phase-space
distributions with a high level of confidence. Thus, the model
demonstrates that the hypothesis of a common origin of Collinder 135
and UBC 7 complies with present-day observational data.
Description:
We acquire the deep census of the two closely situated open clusters
Collinder 135 and UBC 7 based on Gaia DR3 data. We do a search in the
broad vicinity of the clusters to recover evolutionary related
sources, and recover an extended coeval and comoving population
forming an extended surrounding stellar halo. In the catalogue we
provide the list of sources selected as members to the system of
Collinder 135 and UBC 7 (including stellar halo) with membership
probability larger than 60%, along with basic information from Gaia
DR3 (source_id, l, b, plx_err, gmag, bpmag, rpmag), recalculated
(plx_corr is the Gaia EDR3 parallax with parallax zero-point
correction according to Lindegren et al. (2021A&A...649A...4L 2021A&A...649A...4L), pml
and pmb for proper motion in l and b), calculated (membership
probability MP) characteristics and a flag of affiliation F to one of
the clusters of to halo (1 for members of Collinder 135, 2 for UBC 7,
0 for halo).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
members.dat 124 1421 List of sources selected as members to the
system of Collinder 135 and UBC 7
--------------------------------------------------------------------------------
See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: members.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 source_id
22- 34 F13.9 deg GLON Galactic longitude (J2000.0)
37- 49 F13.9 deg GLAT Galactic latitude (J2000.0)
51- 57 F7.5 mas plxcorr Trigonometric parallax (1)
59- 65 F7.5 mas e_plxcorr Gaia DR3 error of trigonometric parallax
67- 75 F9.5 mas/yr pml Proper motion in Galactic longitude
(J2000.0) (2)
78- 85 F8.5 mas/yr pmb Proper motion in Galactic latitude
(J2000.0) (2)
88- 95 F8.5 mag Gmag Gaia DR3 stellar magnitude in G band
98-105 F8.5 mag Bpmag Gaia DR3 stellar magnitude in Bp band
108-115 F8.5 mag Rpmag Gaia DR3 stellar magnitude in Rp band
118-121 F4.2 --- Pmemb Membership probability (3)
124 I1 --- Flag [0/2] Flag of affiliation (4)
--------------------------------------------------------------------------------
Note (1): Trigonometric parallax Gaia DR3 corrected for zero-point bias
according to Lindegren et al., 2021A&A...649A...4L 2021A&A...649A...4L.
Note (2): Proper motions in galactic longitude and latitude are calculated
based on Gaia DR3 astrometrical data.
Note (3): Probability of membership to the system of clusters and halo.
Note (4): Flag of the preferable affiliation as follows:
1 = Collinder 135
2 = UBC 7
0 = halo
--------------------------------------------------------------------------------
Acknowledgements:
Dana Kovaleva, dana(at)inasan.ru
(End) Patricia Vannier [CDS] 24-May-2024