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1. Washington Red (WR) dyes and their imaging applications

   https://doi.org/10.1016/bs.mie.2020.04.027  

   Chen, Wei; Xian, Ming (May 2020, Methods in enzymology)
2. The orbit and stellar masses of the archetype colliding-wind binary WR 140

   https://doi.org/10.1093/mnras/stab1181  

   Thomas, Joshua D; Richardson, Noel D; Eldridge, J J; Schaefer, Gail H; Monnier, John D; Sana, Hugues; Moffat, Anthony F; Williams, Peredur; Corcoran, Michael F; Stevens, Ian R; et al (May 2021, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   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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3. Peeling Back the Layers: Variable Line Polarization in WR+O Binaries

   Fullard, A.G. (March 2021, Astropol 2020: New Era of Multiwavelength Polarimetry)

   null (Ed.)
4. High-Performance WR-4.3 Optically Controlled Variable Attenuator With 60-dB Range

   https://doi.org/10.1109/LMWC.2018.2823589  

   Ren, Jun; Jiang, Zhenguo; Fay, Patrick; Hesler, Jeffrey L.; Tong, Cheuk-Yu E.; Liu, Lei (June 2018, IEEE Microwave and Wireless Components Letters)
5. To binary or not to binary: An analysis of WR 71’s polarized line profiles

   Johnson, R.A. (January 2021, Bulletin of the American Astronomical Society)

   null (Ed.)

   Massive Wolf-Rayet (WR) stars in binary systems may produce supernovae capable of emitting long duration gamma ray bursts. Characterizing the structure of the colliding winds in these systems may help constrain the mass loss and transfer properties and help predict their future evolution. I will present new spectropolarimetric data for the possible WR+O binary system WR 71, collected using RSS at the Southern African Large Telescope. WR 71 is a WN6 whose binary status is unknown, but it displays similar spectropolarimetric variations to the known WR+O binary system V444 Cygni. I investigate the orbital and rotational velocity of WR 71's winds by analyzing its polarized emission line profiles as a function of phase, the first analysis of its kind. I compare the line polarization behavior with predictive models of both colliding wind binaries and single stars with co-rotating interaction regions. Describing the wind structure of WR 71 will help determine the rate of mass loss from the system, an important indicator for LGRB progenitors, and shed light on its binary status. 

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