2020A&A...641A..26D


C.D.S. - SIMBAD4 rel 1.7 - 2020.11.28CET21:55:29

2020A&A...641A..26D - Astronomy and Astrophysics, volume 641A, 26-26 (2020/9-1)

A spectroscopic multiplicity survey of Galactic Wolf-Rayet stars. I. The northern WC sequence.

DSILVA K., SHENAR T., SANA H. and MARCHANT P.

Abstract (from CDS):


Context. It is now well established that the majority of massive stars reside in multiple systems. However, the effect of multiplicity is not sufficiently understood, resulting in a plethora of uncertainties about the end stages of massive-star evolution. In order to investigate these uncertainties, it is useful to study massive stars just before their demise. Classical Wolf-Rayet stars represent the final end stages of stars at the upper-mass end. The multiplicity fraction of these stars was reported to be ∼0.4 in the Galaxy but no correction for observational biases has been attempted.
Aims. The aim of this study is to conduct a homogeneous radial-velocity survey of a magnitude-limited (V≤12) sample of Galactic Wolf-Rayet stars to derive their bias-corrected multiplicity properties. The present paper focuses on 12 northern Galactic carbon-rich (WC) Wolf-Rayet stars observable with the 1.2m Mercator telescope on the island of La Palma.
Methods. We homogeneously measured relative radial velocities (RVs) for carbon-rich Wolf-Rayet stars using cross-correlation. Variations in the derived RVs were used to flag binary candidates. We investigated probable orbital configurations and provide a first correction of observational biases through Monte-Carlo simulations.
Results. Of the 12 northern Galactic WC stars in our sample, seven show peak-to-peak RV variations larger than 10km/s, which we adopt as our detection threshold. This results in an observed spectroscopic multiplicity fraction of 0.58 with a binomial error of 0.14. In our campaign, we find a clear lack of short-period (P≲100d), indicating that a large number of Galactic WC binaries likely reside in long-period systems. Finally, our simulations show that at the 10% significance level, the intrinsic multiplicity fraction of the Galactic WC population is at least 0.72.

Abstract Copyright: © ESO 2020

Journal keyword(s): binaries: spectroscopic - stars: Wolf-Rayet - techniques: radial velocities

Simbad objects: 21

goto Full paper

goto View the reference in ADS

Number of rows : 21

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 M 31 G 00 42 44.330 +41 16 07.50 4.86 4.36 3.44     ~ 11098 1
2 HD 4004 WR* 00 43 28.3971235391 +64 45 35.383738645 10.28 10.718 10.138     WN4-s 184 0
3 M 33 GiG 01 33 50.904 +30 39 35.79 6.17 6.27 5.72     ~ 5214 1
4 HD 16523 WR* 02 41 11.6752293070 +56 43 49.735743590 10.03 10.34 9.99     WC6 126 0
5 HD 17638 WR* 02 52 11.6616623898 +56 56 07.129636750 10.99 10.86 10.41     WC6 112 0
6 NAME Magellanic Clouds GrG 03 00 -71.0           ~ 5793 1
7 NAME LMC G 05 23 34.6 -69 45 22     0.4     ~ 15060 1
8 HD 38282 WR* 05 38 53.3788120199 -69 02 00.896643506   10.98 11.11 11.26   WN5/6h+WN6/7h 151 1
9 HD 269928 WR* 05 38 57.0668705166 -69 06 05.660972436   12.02 11.94 12.00 11.58 WN6/7 121 0
10 WR 21a WR* 10 25 56.5023591737 -57 48 43.517827393     12.67     O2If*/WN5 81 0
11 HD 165763 WR* 18 08 28.4691215895 -21 15 11.182287576 7.16 7.54 7.82 8.55   WC6 271 0
12 HD 168206 WR* 18 19 07.3628284656 -11 37 59.165038875 9.65 9.88 9.10     WC8+O8/9III/V 285 1
13 MR 88 WR* 18 31 02.5171189240 -06 35 49.629115130   15.34 14.19     WC9 38 0
14 THA 20-1 WR* 18 39 17.9036019736 -10 05 30.898511525   13.07 12.43     WC9d 53 0
15 HD 186943 WR* 19 46 15.9393000440 +28 16 19.074048808 9.86 10.50 10.23     WN3+O9.5V 177 1
16 HD 192103 WR* 20 11 53.5274946554 +36 11 50.523501826 7.77 8.13 8.11     WC8+OB: 323 0
17 HD 192641 WR* 20 14 31.7667382048 +36 39 39.597237795 7.80 8.20 7.91     WC7pd+O9V 311 0
18 HD 193793 WR* 20 20 27.9763345925 +43 51 16.289775091 6.90 7.25 6.85 4.58   WC7p+O5 654 1
19 HD 195177 WR* 20 28 22.6627301104 +38 37 18.970997793 13.42 12.67 11.46     WC4+Be 86 0
20 MR 112 WR* 20 35 47.0859278605 +41 22 44.703520146     12.64 12.16   WC5-6e+O8 144 1
21 HD 213049 WR* 22 27 17.8189297929 +56 15 11.768608852   11.71 10.99     WC6 82 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2020A&A...641A..26D and select 'bookmark this link' or equivalent in the popup menu


2020.11.28-21:55:29

© Université de Strasbourg/CNRS

    • Contact