J/MNRAS/488/3024 Globular clusters members with Gaia DR2 (Bustos Fierro+, 2019)
Extraction of globular clusters members with Gaia DR2 astrometry.
Bustos Fierro I.H., Calderon J.H.
<Mon. Not. R. Astron. Soc. 488, 3024-3034 (2019)>
=2019MNRAS.488.3024B 2019MNRAS.488.3024B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Populations, stellar
Keywords: astrometry - globular clusters: general -
globular clusters: individual: NGC 1261, NGC 3201, NGC 6139, NGC 6205,
NGC 6362, NGC 6397, NGC 6712, Pal 13
Abstract:
In this work, we present a method to identify possible members of
globular clusters using data from Gaia DR2. The method consists of two
stages: the first one based on a clustering algorithm, and the second
one based on the analysis of the projected spatial distribution of
stars with different proper motions. In order to confirm that the
clusters members extracted by the method correspond to actual globular
clusters, the spatial distribution, the vector point diagram of the
proper motions, and the colour-magnitude diagrams are analysed. We
apply the developed method to eight clusters: NGC 1261, NGC 3201,
NGC 6139, NGC 6205, NGC 6362, NGC 6397, NGC 6712, and Palomar 13; we
show the number of members extracted, the mean proper motions derived
from them and finally we compare our results with other authors. In
order to analyse the efficiency of the extraction method, we perform
an estimation of the completeness and the degree of contamination of
the extracted members.
Description:
The file Table4.txt contains the list of all the Gaia DR2 sources in
the fields of eight globular clusters. Each source is presented with
its Gaia DR2 source identifier, coordinates, proper motions, G-band
magnitude and the membership status determined from an analysis of
Gaia DR2 positions and proper motions performed in two stages: the
first one based on a clustering algorithm (Sec. 2.1), and the second
one based on the analysis of the projected spatial distribution of
stars with different proper motions (Sec. 2.2).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 90 949872 Membership status of analysed Gaia DR2 sources
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Field Cluster name (1)
9- 27 I19 --- Source Gaia DR2 source identifier
29- 43 F15.11 deg RAdeg Gaia DR2 right ascension (ICRS)
45- 59 F15.11 deg DEdeg Gaia DR2 declination (ICRS)
61- 69 F9.3 mas/yr pmRA* ? Gaia DR2 proper motion in right ascension
direction (pmRA*cosDE)
71- 79 F9.3 mas/yr pmDE ? Gaia DR2 proper motion in declination
direction
81- 87 F7.4 mag Gmag Gaia DR2 G-band mean magnitude
89- 90 A2 --- Status Membership status (2)
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Note (1): Clusters are Pal13, NGC1261, NGC3201, NGC6139, NGC6205, NGC6362,
NGC6397 and NGC6712
Note (2): Membership status as follows:
M1 = Cluster member extracted in first stage
M2 = Cluster member extracted in second stage
FS = Field star
UN = Unknown status due to proper motion not available in Gaia DR2
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Acknowledgements:
Ivan H. Bustos Fierro, ivanbf(at)oac.unc.edu.ar
(End) Patricia Vannier [CDS] 09-Aug-2019