J/MNRAS/386/447 RV catalogue of O-type stars in NGC 6231 (Sana+, 2008)
The massive star binary fraction in young open clusters I. NGC 6231 revisited.
Sana H., Gosset E., Naze Y., Rauw G., Linder N.
<Mon. Not. R. Astron. Soc. 386, 447 (2008)>
=2008MNRAS.386..447S 2008MNRAS.386..447S
ADC_Keywords: Binaries, spectroscopic ; Radial velocities ; Stars, O
Keywords: binaries: close - binaries: spectroscopic - binaries: general -
stars: early-type -
open clusters and associations: individual: NGC 6231 -
open clusters and associations: Sco OB1
Abstract:
We present the results of a long-term high-resolution spectroscopy
campaign on the O-type stars in NGC 6231. We revise the spectral
classification and multiplicity of these objects and we constrain the
fundamental properties of the O-star population. Almost three quarters
of the O-type stars in the cluster are members of a binary system. The
minimum binary fraction is 0.63, with half the O-type binaries having
an orbital period of the order of a few days. The eccentricities of
all the short-period binaries are revised downward, and henceforth
match a normal period-eccentricity distribution. The mass-ratio
distribution shows a large preference for O+OB binaries, ruling out
the possibility that, in NGC 6231, the companion of an O-type star is
randomly drawn from a standard IMF. Obtained from a complete and
homogeneous population of O-type stars, our conclusions provide
interesting observational constraints to be confronted with the
formation and early-evolution theories of O stars.
Description:
Journal of the spectroscopic observations of the NGC6231 O-type stars
studied in the present paper. The two header lines indicate the
considered spectral lines and the adopted rest wavelength (in
Angstroms). The first column indicates the object considered. The
second and third ones gives the heliocentric Julian dates at
mid-exposure and the code of the instrumental setup. The following
columns provide the heliocentric RVs (expressed in km/s) using various
spectral lines. The last two columns provide the mean and 1-sigma
dispersion computed, for a given date, over the quoted lines. Whenever
appropriate, the mean and 1-sigma dispersion for individual lines are
also given at the bottom of each sub-table.
WARNING:
We stress out that the mean and sigma provided for information only,
and might not have a direct physical meaning nor can they necessarily
be directly compared to one another. Indeed, the mean and sigma have
been computed by processing, for each object, the available
measurements for a given line. No correction for e.g. different
numbers of measurements from one line to another was included
(consequently averaging over different phases in a binary system).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3m.dat 176 13 Mean radial velocities
table3d.dat 104 227 Radial velocity data for O stars in NGC 6231
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See also:
J/A+A/315/384 : Binarity among B-stars in NGC 6231 (Raboud, 1996)
J/A+A/325/167 : Geneva photometry in NGC 6231 (Raboud+ 1997)
J/AJ/115/734 : NGC 6231 UBVRI and Hα photometry (Sung+ 1998)
J/A+AS/137/233 : UBVI imaging photometry of NGC 6231 (Baume+, 1999)
J/A+A/454/1047 : XMM view of NGC 6231 open cluster (Sana+, 2006)
J/MNRAS/372/661 : XMM view of NGC 6231: OB stars (Sana+, 2006)
Byte-by-byte Description of file: table3m.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name Object Identifier
12 A1 --- m_Name [ps] p for primary, s for secondary
14- 18 F5.1 km/s HeI4026 ? Mean radial velocity measured on HeI4026
(r.w. 4026.072) (G2)
20- 24 F5.1 km/s SiIV4089 ? Mean radial velocity measured on SiIV4089
(r.w. 4088.863) (G2)
26- 31 F6.1 km/s HeI4144 ? Mean radial velocity measured on HeI4144
(r.w. 4143.759) (G2)
33- 38 F6.1 km/s HeI4388 ? Mean radial velocity measured on HeI4388
(r.w. 4387.928) (G2)
40- 45 F6.1 km/s HeI4471 ? Mean radial velocity measured on HeI4471
(r.w. 4471.512) (G2)
47- 51 F5.1 km/s MgII4481 ? Mean radial velocity measured on MgII4481
(r.w. 4481.228) (G2)
53- 58 F6.1 km/s HeII4542 ? Mean radial velocity measured on HeII4542
(r.w. 4541.590) (G2)
60- 65 F6.1 km/s HeII4686 ? Mean radial velocity measured on HeII5686
(r.w. 4685.682) (G2)
67- 72 F6.1 km/s HeI4921 ? Mean radial velocity measured on HeI4921
(r.w. 4921.929) (G2)
74- 79 F6.1 km/s HeI5876 ? Mean radial velocity measured on HeI5876
(r.w. 5875.620) (G2)
81- 86 F6.1 km/s HeI7065 ? Mean radial velocity measured on HeI7065
(r.w. 7065.190) (G2)
88- 93 F6.1 km/s MeanRV ? Mean radial velocity computed of the
measured lines (G3)
95- 99 F5.1 km/s SigmaRV ? 1 sigma dispersion of the measured RVs (G3)
101-105 F5.1 km/s e_HeI4026 ? 1 sigma dispersion of HeI4026 mean velocity
107-111 F5.1 km/s e_SiIV4089 ? 1 sigma dispersion of SiIV4089 mean velocity
113-117 F5.1 km/s e_HeI4144 ? 1 sigma dispersion of HeI4144 mean velocity
119-123 F5.1 km/s e_HeI4388 ? 1 sigma dispersion of HeI4388 mean velocity
125-129 F5.1 km/s e_HeI4471 ? 1 sigma dispersion of HeI4471 mean velocity
131-135 F5.1 km/s e_MgII4481 ? 1 sigma dispersion of MgII4481 mean velocity
137-141 F5.1 km/s e_HeII4542 ? 1 sigma dispersion of HeII4542 mean velocity
143-147 F5.1 km/s e_HeII4686 ? 1 sigma dispersion of HeII5686 mean velocity
149-153 F5.1 km/s e_HeI4921 ? 1 sigma dispersion of HeI4921 mean velocity
155-159 F5.1 km/s e_HeI5876 ? 1 sigma dispersion of HeI5876 mean velocity
161-165 F5.1 km/s e_HeI7065 ? 1 sigma dispersion of HeI7065 mean velocity
167-171 F5.1 km/s e_MeanRV ? rms uncertainty on Mean (G3)
173-176 F4.1 km/s e_SigmaRV ? rms uncertainty on Sigma (G3)
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Byte-by-byte Description of file: table3d.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name Object Identifier
12 A1 --- n_Name [ps] p for primary, s for secondary
14- 24 F11.3 d HJD Heliocentric Julian Date
26 A1 --- Inst [abcd] Instrument Setup Code (1)
28- 32 F5.1 km/s HeI4026 ? Radial velocity measured on HeI4026
(r.w. 4026.072) (G2)
34- 38 F5.1 km/s SiIV4089 ? Radial velocity measured on SiIV4089
(r.w. 4088.863) (G2)
40- 44 F5.1 km/s HeI4144 ? Radial velocity measured on HeI4144
(r.w. 4143.759) (G2)
46- 50 F5.1 km/s HeI4388 ? Radial velocity measured on HeI4388
(r.w. 4387.928) (G2)
52- 56 F5.1 km/s HeI4471 ? Radial velocity measured on HeI4471
(r.w. 4471.512) (G2)
58- 62 F5.1 km/s MgII4481 ? Radial velocity measured on MgII4481
(r.w. 4481.228) (G2)
64- 68 F5.1 km/s HeII4542 ? Radial velocity measured on HeII4542
(r.w. 4541.590) (G2)
70- 74 F5.1 km/s HeII4686 ? Radial velocity measured on HeII5686
(r.w. 4685.682) (G2)
76- 80 F5.1 km/s HeI4921 ? Radial velocity measured on HeI4921
(r.w. 4921.929) (G2)
82- 86 F5.1 km/s HeI5876 ? Radial velocity measured on HeI5876
(r.w. 5875.620) (G2)
88- 92 F5.1 km/s HeI7065 ? Radial velocity measured on HeI7065
(r.w. 7065.190) (G2)
94- 98 F5.1 km/s MeanRV Mean RV computed of the measured lines
for a given HJD (G3)
100-104 F5.1 km/s SigmaRV ? 1 sigma dispersion of the measured RVs on
a given HJD (G3)
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Note (1): Instrument Setup Code as follows:
a = CAT+CES
b = ESO1.5m + FEROS
c = ESO/MPG2.2m + FEROS
d = CTIO1.5m + BME
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Global notes:
Note (G2): r.w.: rest wavelength (in Angstroms) adopted to compute the RVs
Note (G3): WARNING: the mean and sigma are provided for information only,
and might not have a direct physical meaning nor can they necessarily
be directly compared to one another. Indeed, the mean and sigma have
been computed by processing the available measurements for a given
date. No correction for e.g. different numbers of measurements from
one date to another was included (consequently averaging over
different lines, with possibly different systemic velocities).
--------------------------------------------------------------------------------
Acknowledgements: Hugues Sana, hsana(at)eso.org
References:
Sana et al., 2001A&A...370..121S 2001A&A...370..121S (HD 152248)
Sana et al., 2003A&A...405.1063S 2003A&A...405.1063S (CPD-41 7742)
Sana et al., 2006MNRAS.371...67S 2006MNRAS.371...67S (HD152219)
Sana et al., 2007ApJ...659.1582S 2007ApJ...659.1582S (CPD -41 7733)
Sana et al., 2008NewA...13..202S 2008NewA...13..202S (HD 152218)
(End) Hugues Sana [ESO, Chile], Patricia Vannier [CDS] 16-Feb-2008