Search Publications
Dynamical Mass of the Young Substellar Companion HD 984 B
Dupuy, Trent J.; Kraus, Adam L.; Tran, Quang H. +5 more
Model-independent masses of substellar companions are critical tools to validate models of planet and brown dwarf cooling, test their input physics, and determine the formation and evolution of these objects. In this work, we measure the dynamical mass and orbit of the young substellar companion HD 984 B. We obtained new high-contrast imaging of t…
Speckle Interferometry at SOAR in 2021
Tokovinin, Andrei; Mason, Brian D.; Mendez, Rene A. +1 more
The speckle interferometry program at the the 4.1 m Southern Astrophysical Research Telescope (SOAR), which started in 2008, now has accumulated over 30,300 individual observations of 12,700 distinct targets. Its main goal is to monitor orbital motion of close binaries, including members of high-order hierarchies and low-mass dwarfs in the solar n…
Precise Dynamical Masses of ɛ Indi Ba and Bb: Evidence of Slowed Cooling at the L/T Transition
Dupuy, Trent J.; Brandt, Timothy D.; Li, Yiting +3 more
We report individual dynamical masses of 66.92 ± 0.36 M Jup and 53.25 ± 0.29 M Jup for the binary brown dwarfs ɛ Indi Ba and Bb, measured from long-term (≈10 yr) relative orbit monitoring and absolute astrometry monitoring data on the Very Large Telescope (VLT). Relative astrometry with NACO fully constrains the Keplerian orb…
A Mini-Neptune from TESS and CHEOPS Around the 120 Myr Old AB Dor Member HIP 94235
Latham, David W.; Quinn, Samuel N.; Kane, Stephen R. +36 more
The Transiting Exoplanet Survey Satellite (TESS) mission has enabled discoveries of the brightest transiting planet systems around young stars. These systems are the benchmarks for testing theories of planetary evolution. We report the discovery of a mini-Neptune transiting a bright star in the AB Doradus moving group. HIP 94235 (TOI-4399, TIC 464…
Orbital Elements and Individual Component Masses from Joint Spectroscopic and Astrometric Data of Double-line Spectroscopic Binaries
Anguita-Aguero, Jennifer; Mendez, Rene A.; Clavería, Rubén M. +1 more
We present orbital elements, orbital parallaxes, and individual component masses for 14 spatially resolved double-line spectroscopic binaries derived doing a simultaneous fit of their visual orbit and radial velocity curve. This was done by means of a Markov Chain Monte Carlo code developed by our group that produces posterior distribution functio…
Atmospheric and Fundamental Parameters of Eight Nearby Multiple Stars
Al-Wardat, Mashhoor A.; Abu-Alrob, Enas M.; Hussein, Abdallah M. +4 more
We present the complete set of atmospheric and fundamental parameters, in addition to the masses, for the individual components of eight stellar systems. The list of the systems, whose orbital solutions were published recently, includes seven binaries (HIP 14524, HIP 16025, HIP 46199, HIP 47791, HIP 60444, HIP 61100, HIP 73085) and one triple syst…
SCExAO and Keck Direct Imaging Discovery of a Low-mass Companion Around the Accelerating F5 Star HIP 5319
Currie, Thayne; Tamura, Motohide; Bailey, John I., III +26 more
We present the direct imaging discovery of a low-mass companion to the nearby accelerating F star, HIP 5319, using SCExAO coupled with the CHARIS, VAMPIRES, and MEC instruments in addition to Keck/NIRC2 imaging. CHARIS JHK (1.1-2.4 µm) spectroscopic data combined with VAMPIRES 750 nm, MEC Y, and NIRC2 L p photometry is best matche…
An Adaptive Optics Census of Companions to Northern Stars Within 25 pc with Robo-AO
Baranec, Christoph; Law, Nicholas M.; Riddle, Reed +8 more
In order to assess the multiplicity statistics of stars across spectral types and populations in a volume-limited sample, we censused nearby stars for companions with Robo-AO. We report on observations of 1157 stars of all spectral types within 25 pc with decl. >-13° searching for tight companions. We detected 154 companion candidates with sepa…
The Gliese 86 Binary System: A Warm Jupiter Formed in a Disk Truncated at ≈2 au
Wittenmyer, Robert A.; Horner, Jonathan; Dupuy, Trent J. +12 more
Gliese 86 is a nearby K dwarf hosting a giant planet on a ≈16 day orbit and an outer white dwarf companion on a ≈century-long orbit. In this study we combine radial velocity data (including new measurements spanning more than a decade) with high angular resolution imaging and absolute astrometry from Hipparcos and Gaia to measure the current orbit…
A Jupiter Analog Orbiting The Nearby M Dwarf GJ 463
Cochran, William D.; Endl, Michael; Howard, Andrew W. +8 more
We report the detection of a long-period giant planetary companion to the nearby M3V star GJ 463 (=Ross 690). The detection is based on over ten years of highly-precise radial velocity measurements with the High Resolution Spectrograph at the Hobby-Eberly Telescope and the HIRES spectrograph at Keck. With an orbital period of 10 yr and a minimum m…