J/ApJS/90/83 Binaries in NGC 3201 (Cote+, 1994)
A search for binaries in the globular cluster NGC 3201
Cote P., Welch D.L., Fischer P., Da Costa G.S., Tamblyn P., Seitzer P.
Irwin M.J.
<Astrophys. J. Suppl. Ser. 90, 83 (1994)>
=1994ApJS...90...83C 1994ApJS...90...83C (SIMBAD/NED Reference)
ADC_Keywords: Photometry, CCD ; Clusters, globular ; Radial velocities
Abstract:
We present BV CCD and APM photometry, accurate astrometry and 1859
radial velocities for 1318 stars within ∼36deg of the Galactic
globular cluster NGC 3201. The field and cluster populations separate
unambiguously in two distinct samples since the systemic radial
velocity of NGC 3201 is 494.2km/s. After removal of the 19 known NGC
3201 photometric variables in our sample, we have a database of 930
radial velocities for 420 member giants (276 of which have multiple
velocity measurements) with which to identify spectroscopic binaries
on the basis of radial velocity variations. The mean time span of the
observations is 1.7yr, with coverage up to ∼6yr for our best-studied
stars. Monte Carlo simulations of the observed velocity variations
have provided upperlimits_ to the cluster binary fraction (for
binaries with 0.1≤P≤5-10yr and mass ratios in the range 0.1-1) of
0.06-0.10 (circular orbits) and 0.15-0.18 (eccentric orbits). These
results suggest an incidence of binarism for NGC 3201 consistent with
the corresponding incidence among nearby solar-type stars having
similar periods and mass ratios (0.04-0.08) and that for a small
sample of other globular clusters (0.05-0.12) studied by Hut et al.
(1992PASP..104..981H 1992PASP..104..981H).
The detailed analysis of the cluster dynamics, based on the data
given here, are presented by Cote et al. (1995ApJ...454..788C 1995ApJ...454..788C).
Addresses:
Cote P., Welch D.L. and Fischer P.
Department of Physics and Astronomy, McMaster University,
Hamilton, ON, Canada L8S 4M1
Da Costa G.S.
Anglo-Australian Observatory, P.O. Box 296, Epping, NSW 2121, Australia
Tamblyn P.
Steward Observatory, University of Arizona, Tucson, AZ, 85721
Seitzer P.
Department of Astronomy, University of Michigan, Ann Arbor, MI, 48109
Irwin M.J.
Royal Greenwich Observatory, Madingley Road, Cambridge, CB3 0HA, UK
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2 76 40 Radial velocities for photometric variables
table3 119 930 Radial velocities and photometry
table4 87 889 Radial velocities for NGC 3201 field stars
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Byte-by-byte Description of file: table2
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Bytes Format Units Label Explanations
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1- 2 I2 --- VarID [1/19]+= Star number in this table
5- 6 I2 h RAh Right Ascension J2000 (hours)
8- 9 I2 min RAm Right Ascension J2000 (minutes)
11- 15 F5.2 s RAs Right Ascension J2000 (seconds)
17 A1 --- DE- Declination J2000 (sign)
18- 19 I2 deg DEd Declination J2000 (degrees)
21- 22 I2 arcmin DEm Declination J2000 (minutes)
24- 27 F4.1 arcsec DEs Declination J2000 (seconds)
30- 41 F12.4 d HJD Heliocentric Julian Date of observation
44- 49 F6.2 km/s RVel Radial velocity
51- 55 F5.2 km/s e_RVel Mean error on RVel
59- 64 F6.4 d Period *? Period of variability
67- 68 A2 --- r_RVel *Source of velocity
73- 76 A4 --- ID(Saw) *Designation in Sawyer-Hog (1973)
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Note on Period: it is taken from
Fourcade & Laborde (1966, Atlas y Catalogo de Estrellas Variables
en Cumulos Globulares al sur de 29deg,
La Plata, Asociacion Argentina de Astronomia, or
Sawyer-Hogg (1973, Publ. Dominion Astrophys. Obs. Victoria,
=1973PDDO....3....6S 1973PDDO....3....6S)
Note on r_RVel: the code refers to telescope and instrument,
see column 4 of table 1 in the printed paper
Note on ID(Saw): Variable designation in Sawyer-Hogg's 1973 paper
(1973PDDO....3....6S 1973PDDO....3....6S)
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Byte-by-byte Description of file: table3
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Bytes Format Units Label Explanations
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1- 3 I3 --- Star [1/420]+= Star identification number
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 15 F5.2 s RAs Right ascension (J2000)
17 A1 --- DE- Declination sign
18- 19 I2 deg DEd Declination (J2000)
21- 22 I2 arcmin DEm Declination (J2000)
24- 27 F4.1 arcsec DEs Declination (J2000)
29- 33 F5.2 arcmin Dist Distance from cluster center
35- 46 F12.4 d HJD HJD of radial velocity observation
49- 54 F6.2 km/s RV Heliocentric radial velocity
57- 60 F4.2 km/s e_RV RV uncertainty
63- 68 F6.2 km/s RVmean Weighted mean heliocentric radial velocity
71- 74 F4.2 km/s e_RVmean RVmean uncertainty
77- 81 F5.2 mag Vmag Apparent V magnitude
84- 87 F4.2 mag B-V Apparent B-V color
90- 91 I2 --- o_RV Number of radial velocity measurements
93- 98 F6.2 --- 2_RV Chi-square for radial velocities
100-105 F6.2 --- Chi2RV ? Reduced chi-square for radial velocities
108-113 F6.4 --- Prob [0/1]? Probability of obtaining a chi-square
at least this large purely as a
consequence of measurement error
116-118 A3 --- Src Source of photometry, 'APM' or 'CCD'
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Byte-by-byte Description of file: table4
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Bytes Format Units Label Explanations
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1- 3 I3 --- ID [1/879]+= Identification number
4 A1 --- n_ID '*' if identified as member in another run
6- 7 I2 h RAh Right ascension (J2000.0)
9- 10 I2 min RAm Right ascension (J2000.0)
12- 16 F5.2 s RAs Right ascension (J2000.0)
19 A1 --- DE- Declination sign
20- 21 I2 deg DEd Declination (J2000.0)
23- 24 I2 arcmin DEm Declination (J2000.0)
26- 29 F4.1 arcsec DEs Declination (J2000.0)
30- 36 F7.2 arcmin Dist Distance from cluster center
39- 50 F12.4 d HJD Heliocentric Julian date of observation
53- 58 F6.2 km/s RV Heliocentric Radial Velocity
62- 65 F4.2 km/s e_RV rms uncertainty on RV
68- 72 F5.2 mag Vmag []? V Magnitude
75- 78 F4.2 mag B-V []? B-V Colour
81- 83 A3 --- Phot Source of Photometry (APM or CCD)
86- 87 A2 --- ObsRun Observing Run (1)
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Note (1): LC = Las Campanas; A1/A2 = CTIO + ARGUS
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References:
Cote et al. 1995, ApJ, 454, 788 =1995ApJ...454..788C 1995ApJ...454..788C
Sawyer-Hogg H., 1973, Publ. Dominion Astrophys. Obs. Victoria,
=1973PDDO....3....6S 1973PDDO....3....6S
Origin: AAS CD-ROM series, Volume 2, 1994;
table2 added at CDS (15-Oct-1996)
(End) Lee Brotzman [ADS] 09-Apr-1994, rev. CDS 15-Oct-1996