J/A+A/624/L11 Coma Berenices neighbor moving group (Fuernkranz+, 2019)
Extended stellar systems in the solar neighborhood.
III. Like ships in the night: the Coma Berenices neighbor moving group.
Fuernkranz V., Meingast S., Alves J.
<Astron. Astrophys. 624, L11 (2019)>
=2019A&A...624L..11F 2019A&A...624L..11F (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Positional data
Keywords: stars: kinematics and dynamics - solar neighborhood -
open clusters and associations: individual: Coma Berenices
Abstract:
We report the discovery of a kinematically cold group of stars,
located in the immediate neighborhood of the well-known star cluster
Coma Berenices (Mel 111). The new group identified in tangential
velocity space as measured by Gaia contains at least 177 coeval
members distributed in two subgroups, and appears as a flattened
structure parallel to the plane, stretching for about 50pc. More
remarkably, the new group, which appears to have formed about 300Myr
later than Mel 111 in a different part of the Galaxy, will share
essentially the same volume with the older cluster when the centers of
both groups will be at their closest in 13 Myr. This will result in
the mixing of two unrelated populations with different metallicities.
The phase of cohabitation for these two groups is about 20-30Myr,
after which the two populations will drift apart. We estimate that
temporal cohabitation of such populations is not a rare event in the
disk of the Milky Way, and of the order of once per Galactic
revolution. Our study also unveils the tidal tails of the Mel 111
cluster.
Description:
We present two tables, one contains the final source selection for
Coma Berenices, and the other one contains the final source selection
for the neighbor group of Coma Berenices as presented in the
associated letter. We provide basic Gaia DR2 information which
includes unique source identifiers. Furthermore, also the computed
Galactic Cartesian coordinates, tangential velocities, and
Galactocentric Cylindrical velocities are included.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
coma_ber.dat 157 214 Member selection for Coma Berenices (table A2)
coma_nei.dat 157 177 Member selection for neighbor group (table A2)
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/A+A/621/L3 : Hyades tidal tails with Gaia DR2 (Meingast+, 2019)
J/A+A/622/L13 : Stellar stream in Gaia DR2 discovery (Meingast+, 2019)
Byte-by-byte Description of file: coma_ber.dat coma_nei.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- Source Gaia DR2 Unique source identifier
21- 32 F12.8 deg RAdeg Gaia DR2 Right ascension (ICRS) at epoch 2015.5
34- 45 F12.8 deg DEdeg Gaia DR2 Declination (ICRS) at epoch 2015.5
47- 56 F10.6 mas Plx Gaia DR2 parallax
58- 69 F12.6 mas/yr pmRA* Gaia DR2 Proper motion in RA direction,
pmRA*cosDE
71- 82 F12.6 mas/yr pmDE Gaia DR2 Proper motion in DE direction
84- 93 F10.6 km/s RV ?=- Gaia DR2 Radial velocity
95-101 F7.3 pc X Galactic Cartesian X
103-109 F7.3 pc Y Galactic Cartesian Y
111-117 F7.3 pc Z Galactic Cartesian Z
119-125 F7.3 km/s vRA Velocity along RA
127-133 F7.3 km/s vDE Velocity along DE
135-141 F7.3 km/s vR ?=- Galactocentric Cylindrical vR
143-149 F7.3 km/s vPHI ?=- Galactocentric Cylindrical vPHI
151-157 F7.3 km/s vZ ?=- Galactocentric Cylindrical vZ
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Acknowledgements:
Verena Fuenkranz, verena.fuernkranz(at)univie.ac.at
Stefan Meingast, stefan.meingast(at)univie.ac.at
Joao Alves, joao.alves(at)univie.ac.at
References:
Meingast & Alves, Paper I 2019A&A...621L...3M 2019A&A...621L...3M, Cat. J/A+A/621/L3
Meingast et al., Paper II 2019A&A...622L..13M 2019A&A...622L..13M, Cat. J/A+A/622/L13
(End) Patricia Vannier CDS 11-Apr-2019