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  1. Abstract LMCe055-1 was recently discovered in a survey for Wolf–Rayets (WRs) in the Large Magellanic Cloud, and classified as a WN4/O4, a lower-excitation version of the WN3/O3 class discovered as part of the same survey. Its absolute magnitude precluded it from being a WN4+O4 binary. Optical Gravitational Lensing Experiment photometry shows shallow primary and secondary eclipses with a 2.2 days period. The spectral characteristics and short period pointed to a possible origin due to binary stripping. Such stripped WR binaries should be common but have proven elusive to identify conclusively. In order to establish its nature, we obtained Hubble Space Telescope ultraviolet and Magellan optical spectra, along with imaging. Our work shows that the WR emission and Heiiabsorption arise in one star, and the Heiabsorption in another. The Heicontributor is the primary of the 2.2 days system and exhibits ∼300 km s−1radial velocity variations on that timescale. However, the WR star shows 30–40 km s−1radial velocity variations, with a likely 35 days period and a highly eccentric orbit. Possibly LMCe055-1 is a physical triple, but that would require the 2.2 days pair to have been captured by the WR star. A more likely explanation is that the WR star has an unseen companion in a 35 days orbit and that the 2.2 days pair is in a longer-period orbit about the two. Such examples of multiple systems are well known among massive stars, such as HD 5980. Regardless, we argue that it is highly unlikely that the WR component of the LMCe055-1 system resulted from stripping. 
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  2. Abstract Wolf–Rayet stars (WRs) are evolved massive stars in the brief stage before they undergo core collapse. Not only are they rare, but they also can be particularly difficult to find due to the high extinction in the Galactic plane. This paper discusses the discovery of three new Galactic WRs previously classified as Hαemission stars, but thanks to Gaia spectra, we were able to identify the broad, strong emission lines that characterize WRs. Using the Lowell Discovery Telescope and the DeVeny spectrograph, we obtained spectra for each star. Two are WC9s, and the third is a WN6 + O6.5 V binary. The latter is a known eclipsing system with a 4.4 day period from ASAS-SN data. We calculate absolute visual magnitudes for all three stars to be between −7 and −6, which is consistent with our expectations of these subtypes. These discoveries highlight the incompleteness of the WR census in our local volume of the Milky Way and suggest the potential for future Galactic WR discoveries from Gaia low-dispersion spectra. Furthermore, radial velocity studies of the newly found binary will provide direct mass estimates and orbital parameters, adding to our knowledge of the role that binarity plays in massive star evolution. 
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  3. Free, publicly-accessible full text available February 28, 2026