J/MNRAS/424/1925 Spectroscopic Binarity of O and B type stars (Chini+, 2012)
A spectroscopic survey on the multiplicity of high-mass stars.
Chini R., Hoffmeister V.H., Nasseri A., Stahl O., Zinnecker H.
<Mon. Not. R. Astron. Soc., 424, 1925-1929 (2012)>
=2012MNRAS.424.1925C 2012MNRAS.424.1925C
ADC_Keywords: Binaries, spectroscopic ; Stars, O ; Stars, B-type ;
MK spectral classification
Keywords: binaries: close - binaries: general - binaries: spectroscopic -
stars: early-type - stars: formation
Abstract:
The formation of stars above about 20M☉ and their apparently
high multiplicity remain heavily debated subjects in astrophysics. We
have performed a vast high-resolution radial velocity spectroscopic
survey of about 250 O- and 540 B-type stars in the southern Milky Way
which indicates that the majority of stars (>82%) with masses above
16M☉ form close binary systems while this fraction rapidly drops
to 20% for stars of 3M☉. The binary fractions of O-type stars
among different environment classes are: clusters (72±13%),
associations (73±8%), field (43±13%) and runaways (69±11%). The
high frequency of close pairs with components of similar mass argues
in favour of a multiplicity originating from the formation process
rather than from a tidal capture in a dense cluster. The high binary
frequency of runaway O stars that we found in our survey (69% compared
to 19-26% in previous surveys) points to the importance of ejection
from young star clusters and thus supports the competitive accretion
scenario.
Description:
We have performed a comprehensive spectroscopic survey on a large
representative sample of 249 O- and 581 B-type stars.
Using the high-resolution spectrograph BESO at the Hexapod Telescope
at the Universitatssternwarte Bochum near Cerro Armazones in Chile,
we obtained 3632 multi-epoch optical spectra. The observing period
started in 2009 January and is still going on. The spectra comprise a
wavelength range from 3620 to 8530Å and provide a mean spectral
resolution of R=50000.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 39 830 Spectroscopic results for 248 O- and 581 B-type
stars
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
V/116 : Galactic O star catalog (Maiz-apellaniz+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Star Name
20- 31 A12 --- SpType MK spectral type
34- 35 I2 --- No Number of spectra
37- 39 A3 --- Mult [C SB12 U] Binarity status: Constant,
Spectroscopic Binary or Unknown (1)
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Note (1): Multiplicity status:
C = constant RV
SB1 = spectroscopic binary, primary spectrum only detected
SB2 = spectroscopic binary, 2 spectra detected
U = unknown
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 03-May-2013