J/MNRAS/503/236 UVIT catalog and membership of 6 open clusters (Jadhav+, 2021)
UOCS. III. UVIT catalogue of open clusters with machine learning-based
membership using Gaia EDR3 astrometry.
Jadhav V.V., Pennock C.M., Subramaniam A., Sagar R., Nayak P.K.
<Mon. Not. R. Astron. Soc. 503, 236-253 (2021)>
=2021MNRAS.503..236J 2021MNRAS.503..236J (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Photometry, ultraviolet ; Optical
Keywords: methods: data analysis - catalogues -
Hertzsprung-Russell and colour-magnitude diagrams -
open clusters and associations: individual: Berkeley 67, King 2,
NGC 2420, NGC 2477, NGC 2682, NGC 6940 - ultraviolet: stars
Abstract:
We present a study of six open clusters (Berkeley 67, King 2,
NGC 2420, NGC 2477, NGC 2682 and NGC 6940) using the Ultra Violet
Imaging Telescope (UVIT) aboard ASTROSAT and Gaia EDR3. We present
their Gaia EDR3 membership catalogues and UV photometric catalogues
along with membership probability. We used a supervised machine
learning algorithm along with a Gaussian mixture model and used
combinations of astrometric, photometric and systematic parameters to
train the algorithm. We classified the stars as members, candidates
and field using two such combinations. This generic technique is
robust, reproducible, versatile in various cluster environments and is
applicable to other data-sets. We could detect 200-2500 additional
members using this method with respect to Gaia DR2 studies. We
estimated cluster properties such as mean space velocities, distances,
number of members and core radii. We detected 3 to 700 member stars,
which include blue stragglers, main-sequence and red giants in various
UVIT images of six clusters. We created UV-Optical colour-magnitude
diagrams to find that majority of the sources in NGC 2682 and a few in
NGC 2420, NGC 2477 and NGC 6940 showed excess UV flux. NGC 2682 images
have 10 white dwarf detections in far-UV. The massive cluster NGC 2477
has 92/576 members detected in the far-UV/near-UV, which will be
useful to study the UV properties of stars in the extended turn-off
and in various evolutionary stages from main-sequence to red clump.
Future studies will carry out panchromatic analysis of noteworthy
members detected in this study.
Description:
Gaia membership catalogue and UVIT photometric catalogues.
Objects:
----------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------
04 37 48 +50 46.5 Berkeley 67 = Cl Berkeley 67
00 51 00 +58 11.0 King 2 = Cl King 2
07 38 23 +21 34.4 NGC 2420 = Cl Melotte 69
07 52 10 -38 31.8 NGC 2477 = Cl Melotte 78
08 51 18 +11 48.0 NGC 2682 = M 67
20 34 26 +28 17.0 NGC 6940 = Cl Melotte 232
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
gaia-cat.dat 202 17087 Membership probability of individual stars of
six open clusters with Gaia EDR3 (table B1)
ber67.dat 59 620 UV photometric catalogue of Berkeley 67
king2.dat 59 413 UV photometric catalogue of King 2
ngc2420.dat 42 177 UV photometric catalogue of NGC 2420
ngc2477.dat 67 1763 UV photometric catalogue of NGC 2477
ngc2682.dat 82 1381 UV photometric catalogue of NGC 2682
ngc6940.dat 47 151 UV photometric catalogue of NGC 6940
--------------------------------------------------------------------------------
See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
Byte-by-byte Description of file: gaia-cat.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaEDR3 Gaia EDR3 source_id
21- 39 F19.15 deg RAdeg Gaia EDR3 right ascension (ICRS) at Ep=2016
41- 59 F19.15 deg DEdeg Gaia EDR3 declination (ICRS) at Ep=2016
61- 78 F18.15 mag Gmag ? Gaia EDR3 mean G magnitude
80- 99 F20.17 mag G-RP ? Gaia EDR3 G minus RP colour
101 I1 --- Qual [0/1] Quality filter (see Tab.3 in the paper)
103-122 F20.18 --- PF6 Membership probability using F6
124-143 F20.18 --- PF8 Membership probability using F8
145-165 F21.19 --- PF10 Membership probability using F10
167-188 E22.20 --- PGMM ? Membership probability using GMM
190 A1 --- Class [MCF] Classification as Member, Candidate
and Field (see eq. 5)
192-202 A11 --- Cluster Corresponding cluster (1)
--------------------------------------------------------------------------------
Note (1): 1708 sources for Berkeley_67, 2663 sources for King_2,
1458 sources for NGC_2420, 8341 sources for NGC_2477,
1541 sources for NGC_2682 and 1376 sources for NGC_6940.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ber67.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.5 deg RAdeg Mean right ascension (ICRS) at Ep=2015.5
10- 17 F8.5 deg DEdeg Mean declination (ICRS) at Ep=2015.5
19- 23 F5.2 mag N242W ? UVIT/N242W magnitude (AB)
25- 29 F5.2 mag N242Wsat ? UVIT/N242W magnitude (AB) for saturated stars
31- 34 F4.2 mag e_N242W ? Error in N242W magnitude
36- 40 F5.2 mag N245M ? UVIT/N245M magnitude (AB)
42- 45 F4.2 mag e_N245M ? Error in N245M magnitude
47- 51 F5.3 --- PF6 ? Membership probability using F6
53- 57 F5.3 --- PF10 ? Membership probability using F10
59 A1 --- Class [MCF] Classification as Member, Candidate
and Field
--------------------------------------------------------------------------------
Byte-by-byte Description of file: king2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.5 deg RAdeg Mean right ascension (ICRS) at Ep=2015.5
10- 17 F8.5 deg DEdeg Mean declination (ICRS) at Ep=2015.5
19- 23 F5.2 mag F148W ? UVIT/F148W magnitude (AB)
25- 29 F5.2 mag F148Wsat ? UVIT/F148W magnitude (AB) for saturated stars
31- 34 F4.2 mag e_F148W ? Error in F148W magnitude
36- 40 F5.2 mag N219M ? UVIT/N219M magnitude (AB)
42- 45 F4.2 mag e_N219M ? Error in N219M magnitude
47- 51 F5.3 --- PF6 ? Membership probability using F6
53- 57 F5.3 --- PF10 ? Membership probability using F10
59 A1 --- Class [MCF] Classification as Member, Candidate
and Field
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ngc2420.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.4 deg RAdeg Mean right ascension (ICRS) at Ep=2015.5
10- 17 F8.5 deg DEdeg Mean declination (ICRS) at Ep=2015.5
19- 23 F5.2 mag F148W UVIT/F148W magnitude (AB)
25- 28 F4.2 mag e_F148W Error in F148W magnitude
30- 34 F5.3 --- PF6 ? Membership probability using F6
36- 40 F5.3 --- PF10 ? Membership probability using F10
42 A1 --- Class [MCF] Classification as Member, Candidate
and Field
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ngc2477.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Mean right ascension (ICRS) at Ep=2015.5
11- 19 F9.5 deg DEdeg Mean declination (ICRS) at Ep=2015.5
21- 25 F5.2 mag F148W ? UVIT/F148W magnitude (AB)
27- 31 F5.2 mag F148Wsat ? UVIT/F148W magnitude (AB) for saturated stars
33- 36 F4.2 mag e_F148W ? Error in F148W magnitude
38- 42 F5.2 mag N263M ? UVIT/N263M magnitude (AB)
44- 48 F5.2 mag N263Msat ? UVIT/N263M magnitude (AB) for saturated stars
50- 53 F4.2 mag e_N263M ? Error in N263M magnitude
55- 59 F5.3 --- PF6 ? Membership probability using F6
61- 65 F5.3 --- PF10 ? Membership probability using F10
67 A1 --- Class [MCF] Classification as Member, Candidate
and Field
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ngc2682.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Mean right ascension (ICRS) at Ep=2015.5
11- 18 F8.5 deg DEdeg Mean declination (ICRS) at Ep=2015.5
20- 24 F5.2 mag F148W ? UVIT/F148W magnitude (AB)
26- 30 F5.2 mag F148Wsat ? UVIT/F148W magnitude (AB) for saturated stars
32- 35 F4.2 mag e_F148W ? Error in F148W magnitude
37- 41 F5.2 mag F154W ? UVIT/F154W magnitude (AB)
43- 47 F5.2 mag F154Wsat ? UVIT/F154W magnitude (AB) for saturated stars
49- 52 F4.2 mag e_F154W ? Error in F154W magnitude
54- 58 F5.2 mag F169M ? UVIT/F169M magnitude (AB)
60- 63 F4.1 mag F169Msat ? UVIT/F169M magnitude (AB) for saturated stars
65- 68 F4.2 mag e_F169M ? Error in F169M magnitude
70- 74 F5.3 --- PF6 ? Membership probability using F6
76- 80 F5.3 --- PF10 ? Membership probability using F10
82 A1 --- Class [MCF] Classification as Member, Candidate
and Field
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ngc6940.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.4 deg RAdeg Mean right ascension (ICRS) at Ep=2015.5
10- 17 F8.5 deg DEdeg Mean declination (ICRS) at Ep=2015.5
19- 23 F5.2 mag F169M ? UVIT/F169M magnitude (AB)
25- 28 F4.1 mag F169Msat ? UVIT/F169M magnitude (AB) for saturated stars
30- 33 F4.2 mag e_F169M ? Error in F169M magnitude
35- 39 F5.3 --- PF6 ? Membership probability using F6
41- 45 F5.3 --- PF10 ? Membership probability using F10
47 A1 --- Class [MCF] Classification as Member, Candidate
and Field
--------------------------------------------------------------------------------
Acknowledgements:
Vikrant V. Jadhav, vikrant.jadhav (at) iiap.res.in
References:
Sindhu et al., Paper I 2019ApJ...882...43S 2019ApJ...882...43S
Jadhav et al., Paper II 2019ApJ...886...13J 2019ApJ...886...13J
(End) Patricia Vannier [CDS] 18-Jan-2021