Search Publications
Peering into the formation history of β Pictoris b with VLTI/GRAVITY long-baseline interferometry
Förster Schreiber, N. M.; Genzel, R.; Sturm, E. +65 more
Context. β Pictoris is arguably one of the most studied stellar systems outside of our own. Some 30 yr of observations have revealed a highly-structured circumstellar disk, with rings, belts, and a giant planet: β Pictoris b. However very little is known about how this system came into being.
Aims: Our objective is to estimate the C/O ratio i…
Standing on the Shoulders of Giants: New Mass and Distance Estimates for Betelgeuse through Combined Evolutionary, Asteroseismic, and Hydrodynamic Simulations with MESA
Kobayashi, Chiaki; Nomoto, Ken'ichi; Ireland, Michael +3 more
We conduct a rigorous examination of the nearby red supergiant Betelgeuse by drawing on the synthesis of new observational data and three different modeling techniques. Our observational results include the release of new, processed photometric measurements collected with the space-based Solar Mass Ejection Imager instrument prior to Betelgeuse's …
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…
Evidence for a high mutual inclination between the cold Jupiter and transiting super Earth orbiting π Men
Wyatt, Mark C.; Xuan, Jerry W.
π Men hosts a transiting super Earth (P ≈ 6.27 d, m ≈ 4.82 M⊕, R ≈ 2.04 R⊕) discovered by TESS and a cold Jupiter (P ≈ 2093 d, msin I ≈ 10.02 MJup, e ≈ 0.64) discovered from radial velocity. We use Gaia DR2 and Hipparcos astrometry to derive the star's velocity caused by the orbiting planets and constrain the cold …
Two Directly Imaged, Wide-orbit Giant Planets around the Young, Solar Analog TYC 8998-760-1
Ginski, Christian; Kenworthy, Matthew A.; Mamajek, Eric E. +9 more
Even though tens of directly imaged companions have been discovered in the past decades, the number of directly confirmed multiplanet systems is still small. Dynamical analysis of these systems imposes important constraints on formation mechanisms of these wide-orbit companions. As part of the Young Suns Exoplanet Survey we report the detection of…
The Gaia reference frame for bright sources examined using VLBI observations of radio stars
Lindegren, Lennart
Context. Positions and proper motions of Gaia sources are expressed in a reference frame that ideally should be non-rotating relative to distant extragalactic objects, coincident with the International Celestial Reference System (ICRS), and consistent across all magnitudes. For sources fainter than 16th magnitude, this is achieved through Gaia's d…
Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era
Jasniewicz, G.; Lagarde, N.; Smiljanic, R. +7 more
Context. Li is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors.
Aims: We present the results of a new large Li survey in red giant stars and combine it with surveys from the literature to probe the impact of rotation-induced mixing and thermohaline double-diffusive instability along stella…
A precise architecture characterization of the π Mensae planetary system
Bouchy, F.; Rebolo, R.; Pallé, E. +97 more
Context. The bright star π Men was chosen as the first target for a radial velocity follow-up to test the performance of ESPRESSO, the new high-resolution spectrograph at the European Southern Observatory's Very Large Telescope. The star hosts a multi-planet system (a transiting 4 M⊕ planet at ~0.07 au and a sub-stellar companion on a ~…
Unveiling the β Pictoris system, coupling high contrast imaging, interferometric, and radial velocity data
Genzel, R.; Henning, T.; Meunier, N. +85 more
Context. The nearby and young β Pictoris system hosts a well resolved disk, a directly imaged massive giant planet orbiting at ≃9 au, as well as an inner planet orbiting at ≃2.7 au, which was recently detected through radial velocity (RV). As such, it offers several unique opportunities for detailed studies of planetary system formation and early …