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1. Visual Orbits of Spectroscopic Binaries with the CHARA Array. IV. HD 61859, HD 89822, HD 109510, and HD 191692

   https://doi.org/10.3847/1538-3881/ac9385  

   Lester, Kathryn V.; Schaefer, Gail H.; Fekel, Francis C.; Gies, Douglas R.; Henry, Todd J.; Jao, Wei-Chun; Paredes, Leonardo A.; Hubbard-James, Hodari-Sadiki; Farrington, Christopher D.; Gordon, Kathryn D.; et al (November 2022, The Astronomical Journal)

   Abstract We present the visual orbits of four spectroscopic binary stars, HD 61859, HD 89822, HD 109510, and HD 191692, using long baseline interferometry with the CHARA Array. We also obtained new radial velocities from echelle spectra using the APO 3.5 m, CTIO 1.5 m, and Fairborn Observatory 2.0 m telescopes. By combining the astrometric and spectroscopic observations, we solve for the full, three-dimensional orbits and determine the stellar masses to 1%–12% uncertainty and distances to 0.4%–6% uncertainty. We then estimate the effective temperature and radius of each component star through Doppler tomography and spectral energy distribution analyses. We found masses of 1.4–3.5 M ⊙ , radii of 1.5–4.7 R ⊙ , and temperatures of 6400–10,300 K. We then compare the observed stellar parameters to the predictions of the stellar evolution models, but found that only one of our systems fits well with the evolutionary models. 

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2. Orbital Refinement and Stellar Properties for the HD 9446, HD 43691, and HD 179079 Planetary Systems

   https://doi.org/10.3847/1538-3881/ab7d33  

   Hill, Michelle L.; Močnik, Teo; Kane, Stephen R.; Henry, Gregory W.; Pepper, Joshua; Hinkel, Natalie R.; Dalba, Paul A.; Fulton, Benjamin J.; Stassun, Keivan G.; Rosenthal, Lee J.; et al (May 2020, The Astronomical Journal)

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3. Accurate effective temperatures of the metal-poor benchmark stars HD 140283, HD 122563, and HD 103095 from CHARA interferometry

   https://doi.org/10.1093/mnrasl/sly010  

   Karovicova, I; White, T R; Nordlander, T; Lind, K; Casagrande, L; Ireland, M J; Huber, D; Creevey, O; Mourard, D; Schaefer, G H; et al (January 2018, Monthly Notices of the Royal Astronomical Society: Letters)
4. Probing the Inner Disk Emission of the Herbig Ae Stars HD 163296 and HD 190073

   https://doi.org/10.3847/1538-4357/aaef2c  

   Setterholm, Benjamin R.; Monnier, John D.; Davies, Claire L.; Kreplin, Alexander; Kraus, Stefan; Baron, Fabien; Aarnio, Alicia; Berger, Jean-Philippe; Calvet, Nuria; Curé, Michel; et al (December 2018, The Astrophysical Journal)
5. The Transformative Journey of HD 93521

   https://doi.org/10.3847/1538-3881/ac43be  

   Gies, Douglas R.; Shepard, Katherine; Wysocki, Peter; Klement, Robert (January 2022, The Astronomical Journal)

   Abstract HD 93521 is a massive, rapidly rotating star that is located about 1 kpc above the Galactic disk, and the evolutionary age for its estimated mass is much less than the time of flight if it was ejected from the disk. Here we present a reassessment of both the evolutionary and kinematical timescales for HD 93521. We calculate a time of flight of 39 ± 3 Myr based upon the distance and proper motions from Gaia EDR3 and a summary of radial velocity measurements. We then determine the stellar luminosity using a rotational model combined with the observed spectral energy distribution and distance. A comparison with evolutionary tracks for rotating stars from Brott et al. yields an evolutionary age of about 5 ± 2 Myr. We propose that the solution to the timescale discrepancy is that HD 93521 is a stellar merger product. It was probably ejected from the Galactic disk as a close binary system of lower-mass stars that eventually merged to create the rapidly rotating and single massive star we observe today. 

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