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Title: The orbit and stellar masses of the archetype colliding-wind binary WR 140
ABSTRACT We present updated orbital elements for the Wolf–Rayet (WR) binary WR 140 (HD 193793; WC7pd  + O5.5fc). The new orbital elements were derived using previously published measurements along with 160 new radial velocity measurements across the 2016 periastron passage of WR 140. Additionally, four new measurements of the orbital astrometry were collected with the CHARA Array. With these measurements, we derive stellar masses of $M_{\rm WR} = 10.31\pm 0.45 \, \mathrm{M}_\odot$ and $M_{\rm O} = 29.27\pm 1.14 \, \mathrm{M}_{\odot }$. We also include a discussion of the evolutionary history of this system from the Binary Population and Spectral Synthesis model grid to show that this WR star likely formed primarily through mass-loss in the stellar winds, with only a moderate amount of mass lost or transferred through binary interactions.
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Award ID(s):
1636624 1715788 2009489 1908026
Publication Date:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Page Range or eLocation-ID:
5221 to 5230
Sponsoring Org:
National Science Foundation
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