Search Publications
VLTI/GRAVITY Observations of AF Lep b: Preference for Circular Orbits, Cloudy Atmospheres, and a Moderately Enhanced Metallicity
Pueyo, Laurent; Henning, Th.; Mollière, Paul +26 more
Direct imaging observations are biased toward wide-separation, massive companions that have degenerate formation histories. Although the majority of exoplanets are expected to form via core accretion, most directly imaged exoplanets have not been convincingly demonstrated to follow this formation pathway. We obtained new interferometric observatio…
Orbits of Six Triple Systems
Tokovinin, Andrei
Joint analysis of position measurements and radial velocities of six triple stellar systems is conducted to determine their inner and/or outer orbits. Accumulation of such data is needed to study the architecture of stellar hierarchies and its relation to the formation mechanisms. The inner periods in the six systems (HIP 11783, 64836, 72423, 8472…
Discovery of a Jupiter Analog Misaligned to the Inner Planetary System in HD 73344
Huber, Daniel; Saunders, Nicholas; Fulton, Benjamin J. +6 more
We present the discovery of a Jupiter-like planet, HD 73344 d (
On the Orbit of the Binary Brown Dwarf Companion GL229 Ba and Bb
Henning, Thomas; Mérand, Antoine; Johnstone, Doug +21 more
The companion GL229B was recently resolved by Xuan et al. as a tight binary of two brown dwarfs (Ba and Bb) through VLTI-GRAVITY interferometry and Very Large Telescope-CRIRES+ radial velocity (RV) measurements. Here, we present Bayesian models of the interferometric and RV data in additional detail, along with an updated outer orbit of the brown …
Direct-imaging Discovery of a Substellar Companion Orbiting the Accelerating Variable Star HIP 39017
Salama, Maïssa; Currie, Thayne; Lewis, Briley L. +23 more
We present the direct-imaging discovery of a substellar companion (a massive planet or low-mass brown dwarf) to the young, γ Doradus (γ Dor)-type variable star HIP 39017 (HD 65526). The companion's SCExAO/CHARIS JHK (1.1–2.4 µm) spectrum and Keck/NIRC2 $L^{\prime} $ photometry indicate that it is an L/T transition object. A comparison of the…
Observations with the Differential Speckle Survey Instrument. XI. First Year of Observations from Apache Point Observatory
Majewski, Steven R.; Henry, Todd J.; Chanover, Nancy J. +18 more
The Differential Speckle Survey Instrument (DSSI) was relocated to the Astrophysical Research Consortium 3.5 m telescope at Apache Point Observatory (APO) in early 2022. Here we present results from the first year of observations along with an updated instrument description for DSSI at APO, including a detailed description of a new internal slit m…
Dynamical Architectures of S-type Transiting Planets in Binaries. I. Target Selection Using Hipparcos and Gaia Proper Motion Anomalies
Tan, Thiam-Guan; Huber, Daniel; Weiss, Lauren M. +16 more
The effect of stellar multiplicity on planetary architecture and orbital dynamics provides an important context for exoplanet demographics. We present a volume-limited catalog of up to 300 pc of 66 stars hosting planets and planet candidates from Kepler, K2, and TESS with significant Hipparcos-Gaia proper motion anomalies, which indicates the pres…
VLTI/GRAVITY Provides Evidence the Young, Substellar Companion HD 136164 Ab Formed Like a "Failed Star"
Lutz, D.; Genzel, R.; Sturm, E. +94 more
Young, low-mass brown dwarfs orbiting early-type stars, with low mass ratios (q ≲ 0.01), appear to be intrinsically rare and present a formation dilemma: could a handful of these objects be the highest-mass outcomes of "planetary" formation channels (bottom up within a protoplanetary disk), or are they more representative of the lowest-mass "faile…
A Testbed for Tidal Migration: The 3D Architecture of an Eccentric Hot Jupiter HD 118203 b Accompanied by a Possibly Aligned Outer Giant Planet
Huber, Daniel; Claytor, Zachary R.; Saunders, Nicholas +32 more
Characterizing outer companions to hot Jupiters plays a crucial role in deciphering their origins. We present the discovery of a long-period giant planet, HD 118203 c (
Verification of Astrometrically Accelerating Stars from Hipparcos and Gaia. I. Methodology and Application to HIP 44842
Tokovinin, Andrei; Makarov, Valeri V.
A large number of candidate binary stars with apparent acceleration on the sky has emerged from analysis of astrometric data collected by the Hipparcos, Tycho-2, and Gaia space missions. Although the apparent acceleration can serve as a relatively reliable indicator of binarity, it provides scarce information about the orbital and physical paramet…