Search Publications
Gaia Data Release 3. Astrometric orbit determination with Markov chain Monte Carlo and genetic algorithms: Systems with stellar, sub-stellar, and planetary mass companions
Holl, B.; Sahlmann, J.; Sozzetti, A. +8 more
Context. The astrometric discovery of sub-stellar mass companions orbiting stars is exceedingly hard due to the required sub-milliarcsecond precision, limiting the application of this technique to only a few instruments on a target-per-target basis and to the global astrometry space missions HIPPARCOS and Gaia. The third Gaia data release (Gaia DR…
Direct imaging and astrometric detection of a gas giant planet orbiting an accelerating star
Burrows, Adam; Currie, Thayne; Kwon, Jungmi +31 more
Direct imaging of gas giant exoplanets provides information on their atmospheres and the architectures of planetary systems. However, few planets have been detected in blind surveys with direct imaging. Using astrometry from the Gaia and Hipparcos spacecraft, we identified dynamical evidence for a gas giant planet around the nearby star HIP 99770.…
AF Lep b: The lowest-mass planet detected by coupling astrometric and direct imaging data
Kervella, P.; D'Orazi, V.; Zurlo, A. +6 more
Aims: Using the direct-imaging technique, we searched for low-mass companions around the star AF Lep, which presents a significant proper-motion anomaly (PMa) signal obtained from the comparison of HIPPARCOS and Gaia eDR3 catalogs.
Methods: We observed AF Lep in two epochs with VLT/SPHERE using its subsystems IFS and IRDIS in the near-in…
Direct imaging discovery of a super-Jovian around the young Sun-like star AF Leporis
De Rosa, Robert J.; Nielsen, Eric L.; Hirsch, Lea A. +5 more
Context. Expanding the sample of directly imaged companions to nearby, young stars that are amenable to detailed astrometric and spectroscopic studies is critical for the continued development and validation of theories of their evolution and atmospheric processes.
Aims: The recent release of the Gaia astrometric catalog allows us to efficien…
Astrometric Accelerations as Dynamical Beacons: A Giant Planet Imaged inside the Debris Disk of the Young Star AF Lep
Jensen-Clem, Rebecca; Crepp, Justin R.; Zhou, Yifan +13 more
We present the direct-imaging discovery of a giant planet orbiting the young star AF Lep, a 1.2 M ⊙ member of the 24 ± 3 Myr β Pic moving group. AF Lep was observed as part of our ongoing high-contrast imaging program targeting stars with astrometric accelerations between Hipparcos and Gaia that indicate the presence of substellar compa…
Astrometric Accelerations as Dynamical Beacons: Discovery and Characterization of HIP 21152 B, the First T-dwarf Companion in the Hyades
Magnier, Eugene A.; Jensen-Clem, Rebecca; Crepp, Justin R. +28 more
Benchmark brown dwarf companions with well-determined ages and model-independent masses are powerful tools to test substellar evolutionary models and probe the formation of giant planets and brown dwarfs. Here, we report the independent discovery of HIP 21152 B, the first imaged brown dwarf companion in the Hyades, and conduct a comprehensive orbi…
The Fifth Catalogue of Nearby Stars (CNS5)
Reffert, Sabine; Golovin, Alex; Vani, Akash +3 more
Context. We present the compilation of the Fifth Catalogue of Nearby Stars (CNS5), based on astrometric and photometric data from Gaia EDR3 and HIPPARCOS and supplemented with parallaxes from ground-based astrometric surveys carried out in the infrared.
Aims: The aim of the CNS5 is to provide the most complete sample of objects in the solar n…
Gaia Data Release 3. GRVS photometry from the RVS spectra
Smith, M.; Caffau, E.; Jordi, C. +38 more
Context.Gaia Data Release 3 (DR3) contains the first release of magnitudes estimated from the integration of Radial Velocity Spectrometer (RVS) spectra for a sample of about 32.2 million stars brighter than GRVS ∼ 14 mag (or G ∼ 15 mag).
Aims: In this paper, we describe the data used and the approach adopted to derive and validate …
Binarity and beyond in A stars - I. Survey description and first results of VLTI/GRAVITY observations of VAST targets with high Gaia-Hipparcos accelerations
Katz, Boaz; Waisberg, Idel; Klein, Ygal
The connection between the multiplicity of A stars and that of their white dwarf (WD) descendants is not known and the observational mappings of both multiplicities are far from complete. We are conducting an interferometric survey with VLTI/GRAVITY of 20 out of 108 southern A stars within the VAST sample which show large Gaia-Hipparcos proper mot…
A deep-learning search for technosignatures from 820 nearby stars
de Pater, Imke; Gajjar, Vishal; Siemion, Andrew P. V. +14 more
The goal of the search for extraterrestrial intelligence (SETI) is to quantify the prevalence of technological life beyond Earth via their `technosignatures'. One theorized technosignature is narrowband Doppler drifting radio signals. The principal challenge in conducting SETI in the radio domain is developing a generalized technique to reject hum…