J/MNRAS/416/817 RV catalog of O-type stars in IC 2944 and Cen OB2 (Sana+, 2011)
The massive star binary fraction in young open clusters.
III. IC 2944 and the Cen OB2 association.
Sana H., James G., Gosset E.
<Mon. Not. R. Astron. Soc. 416, 817 (2011)>
=2011MNRAS.416..817S 2011MNRAS.416..817S
ADC_Keywords: Clusters, open ; Binaries, spectroscopic ; Radial velocities ;
Stars, O
Keywords: binaries: close - binaries: spectroscopic - binaries: general -
stars: early-type -
open clusters and associations: individual: (IC 2944, Cen OB2)
Abstract:
Using an extended set of multi-epoch high resolution high
signal-to-noise ratio optical spectra, we re-address the multiplicity
properties of the O-type stars in IC 2944 and in the Cen OB2
association. We present new evidence of binarity for five objects and
we confirm the multiple nature of another two. We derive the first
orbital solutions for HD 100099, HD 101436 and HD 101190 and we
provide additional support for HD 101205 being a quadruple system. The
minimal spectroscopic binary fraction in our sample is fmin=0.57.
Using numerical simulations, we show that the detection rate of our
observational campaign is close to 90%, leaving thus little room for
undetected spectroscopic binary systems. The statistical properties of
the O-star population in IC 2944 are similar, within the
uncertainties, to the results obtained in the earlier papers in this
series despite the fact that sample size effects limit the
significance of the comparison. Using newly derived spectroscopic
parallaxes, we reassess the distance to IC 2944 and obtained
2.3±0.3kpc, in agreement with previous studies. We also confirm
that, as far as the O stars are concerned, the IC 2944 cluster is most
likely a single entity.
Description:
Journal of the spectroscopic observations of the IC2944/Cen OB2 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.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 57 12 Star list
table2.dat 134 153 Radial velocity data for O stars in IC2944/Cen OB2
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See also:
J/MNRAS/386/447 : RV catalogue of O-type stars in NGC 6231 (Sana+, 2008)
J/MNRAS/400/1479 : RV catalogue of O-type stars in NGC 6611 (Sana+, 2009)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Star name
13- 14 I2 h RAh Simbad Hour of Right Ascension (J2000.0)
16- 17 I2 min RAm Simbad Minute of Right Ascension (J2000.0)
19- 22 F4.1 s RAs Simbad Second of Right Ascension (J2000.0)
24 A1 --- DE- Simbad Sign of the Declination (J2000.0)
25- 26 I2 deg DEd Simbad Degree of Declination (J2000.0)
28- 29 I2 arcmin DEm Simbad Arcminute of Declination (J2000.0)
31- 32 I2 arcsec DEs Simbad Arcsecond of Declination (J2000.0)
34- 38 F5.2 mag Bmag Simbad B band magnitude
40- 44 F5.2 mag Vmag Simbad V band magnitude
46- 55 A10 --- SpType Simbad MK spectral type
57 A1 --- Note [*] * indicates that values are for the pair,
not for individual components
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Object Identifier
12 A1 --- m_Name [ps] Component (primary/secondary)
14- 24 F11.3 d HJD Heliocentric Julian Date
26 A1 --- Inst Instrument Setup Code (1)
28- 34 F7.2 km/s HeI4026 ?=- RV measured on HeI4026 (r.w. 4026.072)(2)
35 A1 --- u_HeI4026 Uncertainty flag on HeI4026
37- 43 F7.2 km/s SiIV4089 ?=- RV measured on SiIV4089 (r.w. 4088.863)(2)
45- 51 F7.2 km/s HeI4144 ?=- RV measured on HeI4144 (r.w. 4143.759)(2)
52 A1 --- u_HeI4144 Uncertainty flag on HeI4144
54- 60 F7.2 km/s HeII4200 ?=- RV measured on HeI4388 (r.w. 4199.830)(2)
62- 68 F7.2 km/s HeI4388 ?=- RV measured on HeI4471 (r.w. 4387.928)(2)
70- 76 F7.2 km/s HeI4471 ?=- RV measured on MgII4481 (r.w. 4471.512)(2)
78- 84 F7.2 km/s MgII4481 ?=- RV measured on HeII4542 (r.w. 4481.228)(2)
86- 92 F7.2 km/s HeII4542 ?=- RV measured on HeII5686 (r.w. 4541.590)(2)
94-100 F7.2 km/s HeII4686 ?=- RV measured on HeI4921 (r.w. 4685.682)(2)
102-108 F7.2 km/s HeI4921 ?=- RV measured on HeII5412 (r.w. 4921.929)(2)
109 A1 --- u_HeI4921 Uncertainty flag on HeI4921
111-117 F7.2 km/s HeII5412 ?=- RV measured on HeI5876 (r.w. 5411.620)(2)
119-125 F7.2 km/s HeI5876 ?=- RV measured on HeI7065 (r.w. 5875.620)(2)
126 A1 --- u_HeI5876 Uncertainty flag on HeI5876
128-134 F7.2 km/s HeI7065 ?=- RV measured on HeI7065 (r.w. 7065.190)(2)
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Note (1): Instrument Code as follows:
a = ESO2.2m + FEROS
b = VLT + UVES
Note (2): r.w.: rest wavelength (in Angstroms), adopted to compute the RVs
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Acknowledgements:
Hugues Sana, H.Sana(at)uva.nl
References:
Sana et al., Paper I, 2008MNRAS.386..447S 2008MNRAS.386..447S, Cat. J/MNRAS/386/447
Sana et al., Paper II, 2009MNRAS.400.1479S 2009MNRAS.400.1479S, Cat. J/MNRAS/400/1479
(End) Hugues Sana [UvA, NL], Patricia Vannier [CDS] 04-Apr-2011