Search Publications
A Dynamical Mass of 70 ± 5 MJup for Gliese 229B, the First T Dwarf
Dupuy, Trent J.; Bardalez Gagliuffi, Daniella C.; Bowler, Brendan P. +4 more
We combine Keck/HIRES radial velocities, imaging with HiCIAO/Subaru and the Hubble Space Telescope, and absolute astrometry from Hipparcos and Gaia to measure a dynamical mass of 70 ± 5 ${M}_{\mathrm{Jup}}$ for the brown dwarf companion to Gl 229. Gl 229B was the first imaged brown dwarf to show clear signs of methane in its atmosphere. Cooling mo…
Systematic Phase Curve Study of Known Transiting Systems from Year One of the TESS Mission
Latham, David W.; Kane, Stephen R.; Fetherolf, Tara +14 more
We present a systematic phase curve analysis of known transiting systems observed by the Transiting Exoplanet Survey Satellite (TESS) during year one of the primary mission. Using theoretical predictions for the amplitude of the planetary longitudinal atmospheric brightness modulation, stellar ellipsoidal distortion and Doppler boosting, as well a…
The Gemini Planet Imager Exoplanet Survey: Dynamical Mass of the Exoplanet β Pictoris b from Combined Direct Imaging and Astrometry
Duchêne, Gaspard; Esposito, Thomas M.; Oppenheimer, Rebecca +51 more
We present new observations of the planet β Pictoris b from 2018 with the Gemini Planet Imager (GPI), the first GPI observations following conjunction. Based on these new measurements, we perform a joint orbit fit to the available relative astrometry from ground-based imaging, the Hipparcos Intermediate Astrometric Data (IAD), and the Gaia DR2 pos…
An Updated Visual Orbit of the Directly Imaged Exoplanet 51 Eridani b and Prospects for a Dynamical Mass Measurement with Gaia
Duchêne, Gaspard; Esposito, Thomas M.; Hom, Justin +51 more
We present a revision to the visual orbit of the young, directly imaged exoplanet 51 Eridani b using four years of observations with the Gemini Planet Imager. The relative astrometry is consistent with an eccentric (e={0.53}-0.13+0.09) orbit at an intermediate inclination (i={136}-11+10 °), although circ…
Speckle Interferometry at SOAR in 2019
Tokovinin, Andrei; Horch, Elliott P.; Mason, Brian D. +2 more
The results of speckle-interferometric observations at the 4.1 m Southern Astrophysical Research Telescope in 2019 are given, totaling 2555 measurements of 1972 resolved pairs with separations from 15 mas (median 0"21) and magnitude difference up to 6 mag, and non-resolutions of 684 targets. We resolved for the first time 90 new pairs or subsystem…
Speckle Interferometry of Nearby Multiple Stars: 2007-2019 Positional Measurements and Orbits of Eight Objects
Dyachenko, V.; Beskakotov, A.; Maksimov, A. +4 more
The orbits of eight systems with low-mass components (HIP 14524, HIP 16025, HIP 28671, HIP 46199, HIP 47791, HIP 60444, HIP 61100, and HIP 73085) are presented. Speckle interferometric data were obtained at the 6 m Big Telescope Alt-azimuth Special Astrophysical Observatory of the Russian Academy of Sciences (BTA SAO RAS) from 2007 to 2019. New da…
Orbits for Eight Binaries
Cvetković, Z.; Pavlović, R.
The subject of the present paper is the analysis of the orbital solutions for eight binaries: WDS 02402+0436 = HDS 347, WDS 02552+5950 = MLR 520, WDS 03119+6131 = HDS 407, WDS 04570+7350 = YSC 145, WDS 05202+4105 = HDS 701, WDS 06467+0822 = HDS 940AB, WDS 08259-1623 = HDS 1199, and WDS 22550+5132 = HU 785. Seven orbits are determined for the first…
Spectroscopic Orbits of Subsystems in Multiple Stars. VII.
Tokovinin, Andrei
Spectroscopic orbits of main-sequence stars HIP 3150A, 6873B, 11537A, 22531A, 22534B, 31089B, 49336A, 104833C, and 107731A belonging to eight multiple systems are determined from high-resolution spectra taken with CHIRON. Two of those are twins with mass ratios above 0.95. HIP 11537 is a young three-tier quadruple system with inner periods of 22.3…
Two-epoch Orbit Estimation for Wide Binaries Resolved in Hipparcos and Gaia
Makarov, Valeri V.
The Hipparcos catalog and its Double and Multiple System Annex (DMSA) lists 4099 components with individual proper motions and coordinates on the epoch 1991.25. Many of these long-period binary stars are also present in Gaia Data Release 2 (DR2). Using the available relative positions and proper motions separated by 24.25 yr, the equations of rela…
The Improved Orbit Solution and Component Masses of bet LMi
Wang, Xiaoli; Fu, Yanning; Xia, Fang
bet LMi is a double-lined visual binary with an orbital period of ∼39 yr. Via a simultaneous fitting to both astrometric and radial velocity measurements, we give a complete and improved orbit solution with high precision. Then, the component masses are precisely determined as 2.98 ± 0.10 M⊙ and 1.92 ± 0.04 M⊙ with a relative…