J/AJ/153/134 Proper motions and photometry of stars in NGC 3201 (Sariya+, 2017)
A proper motions study of the globular cluster NGC 3201.
Sariya D.P., Jiang I.-G., Yadav R.K.S.
<Astron. J., 153, 134-134 (2017)>
=2017AJ....153..134S 2017AJ....153..134S (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Proper motions ; Photometry, UBVRI
Keywords: astrometry - catalogs - globular clusters: individual: NGC 3201
Abstract:
With a high value of heliocentric radial velocity, a retrograde orbit,
and suspected to have an extragalactic origin, NGC 3201 is an
interesting globular cluster for kinematical studies. Our purpose is
to calculate the relative proper motions (PMs) and membership
probability for the stars in the wide region of globular cluster NGC
3201. PM based membership probabilities are used to isolate the
cluster sample from the field stars. The membership catalog will help
address the question of chemical inhomogeneity in the cluster. Archive
CCD data taken with a wide-field imager (WFI) mounted on the ESO 2.2m
telescope are reduced using the high-precision astrometric software
developed by Anderson et al. for the WFI images. The epoch gap between
the two observational runs is ∼14.3 years. To standardize the BVI
photometry, Stetson's secondary standard stars are used. The CCD data
with an epoch gap of ∼14.3 years enables us to decontaminate the
cluster stars from field stars efficiently. The median precision of
PMs is better than ∼0.8mas/yr for stars having V<18mag that increases
up to ∼1.5mas/yr for stars with 18<V<20mag. Kinematic membership
probabilities are calculated using PMs for stars brighter than
V∼20mag. An electronic catalog of positions, relative PMs, BVI
magnitudes, and membership probabilities in the ∼19.7x17arcmin2
region of NGC 3201 is presented. We use our membership catalog to
identify probable cluster members among the known variables and X-ray
sources in the direction of NGC 3201.
Description:
To determine the PMs of the stars in this work, we used archive images
(http://archive.eso.org/eso/eso_archive_main.html) from observations
made with the 2.2m ESO/MPI telescope at La Silla, Chile. This
telescope contains a mosaic camera called the Wide-Field Imager (WFI),
consisting of 4*2 (i.e., 8 CCD chips). Since each CCD has an array of
2048*4096 pixels, WFI ultimately produces images with a 34*33arcmin2
field of view.
The observational run of the first epoch contains two images in B,V
and I bands, each with 240s exposure time observed on 1999 December
05. In the second epoch, we have 35 images with 40s exposure time
each in V filter observed during the period of 2014 April 02-05. Thus
the epoch gap between the data is ∼14.3 years.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 13 14 Membership probability of the known variables
in the direction of NGC 3201 and X-ray sources
from Webb et al. 2006 (Cat. J/A+A/445/155)
table4.dat 130 8322 The membership catalog for NGC 3201
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See also:
VII/202 : Globular Clusters in the Milky Way (Harris, 1997)
J/ApJ/801/69 : EWs for giant star members of NGC3201 (Mucciarelli+, 2015)
J/A+A/584/A59 : Proper motions and membership in NGC 6366 (Sariya+, 2015)
J/other/RMxAA/50.307 : RR Lyr light curves in NGC 3201 (Arellano Ferro+, 2014)
J/MNRAS/430/3350 : Proper motions and membership in NGC 3766 (Yadav+, 2013)
J/AcA/62/357 : Proper motions in 6 globular clusters (Zloczewski+, 2012)
J/A+A/543/A87 : Stars proper motions and photometry in M55 (Sariya+, 2012)
J/A+A/497/371 : UBVI photometry of NGC 3201 (Kravtsov+, 2009)
J/A+A/484/609 : BVI photometry and proper motions in M67 (Yadav+, 2008)
J/A+A/445/155 : XMM count-rates in M 55 and NGC 3201 (Webb+, 2006)
J/AJ/123/279 : VI Photometry and Variables in NGC 3201 (von Braun+, 2002)
J/A+AS/131/89 : NGC 1750 + NGC 1758 proper motions (Tian+ 1998)
J/ApJ/454/788 : Radial velocities and BV photometry of NGC 3201 (Cote+ 1995)
J/ApJS/90/83 : Binaries in NGC 3201 (Cote+, 1994)
http://archive.eso.org/eso/eso_archive_main.html : ESO Science Archive
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1 A1 --- f_Sce [VX] Flag on Source (V=known variable in the
direction of NGC 3201; X=X-ray source from
Webb et al. 2006, Cat. J/A+A/445/155)
2- 4 I3 --- Sce Identification number of the source (1)
6- 8 I3 % Mm ? Membership probability
10- 13 I4 --- Star ? Star number in our catalog
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Note (1): The variable stars of NGC 3201 have been compiled on Clement's webpage
of the catalog of variable stars in globular clusters
(http://www.astro.utoronto.ca/~cclement/cat/C1015m461). Recently some new
variables were detected by Kaluzny et al. (2016AcA....66...31K 2016AcA....66...31K). We found
four variable stars in common with our catalog. V137 comes from the
variables listed in Kaluzny et al. (2016AcA....66...31K 2016AcA....66...31K), and the
coordinates of the other three variables have been taken from Clement's
webpage.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Star [1/8322] Running sequential number (ID)
6- 7 I2 h RAh Hour of Right Ascension (J2000)
9- 10 I2 min RAm Minute of Right Ascension (J2000)
12- 16 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- Sign of the Declination (J2000)
19- 20 I2 deg DEd Degree of Declination (J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000)
30- 38 F9.4 pix Xpos [1544.4/4979.9] X position in CCD pixels
40- 48 F9.4 pix Ypos [247.47/4516.05] Y position in CCD pixels
50- 58 F9.4 mas/yr pmRA [-104.1/76.65] Relative proper motion along RA
µαcos(δ)
60- 65 F6.4 mas/yr e_pmRA [0.04/2] rms uncertainty on pmRA
σµαcos(δ)
67- 74 F8.4 mas/yr pmDE [-70.9/34.47] Relative proper motion along DEC
µδ
76- 81 F6.4 mas/yr e_pmDE [0.06/2] rms uncertainty on pmDE
σµδ
83- 89 F7.4 mag Bmag [12.55/21.62] Johnson B magnitude
91- 96 F6.4 mag e_Bmag [0/0.17] rms uncertainty on B mag σB
98-104 F7.4 mag Vmag [11.76/20.1] Johnson V magnitude
106-111 F6.4 mag e_Vmag [0.0001/0.19] rms uncertainty on V mag σV
113-119 F7.4 mag Imag [9.93/19.12] Cousins I magnitude
121-126 F6.4 mag e_Imag [0.0002/0.2] rms uncertainty on I mag σI
128-130 I3 % Mm [0/100] Proper-motion membership probability
Pµ (please refer to Section 3 in the paper
for details)
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 26-Jul-2017