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View article: Characterization of the Host Binary of the Directly Imaged Exoplanet HD 143811 AB b
Characterization of the Host Binary of the Directly Imaged Exoplanet HD 143811 AB b Open
HD 143811 AB is the host star to the directly imaged planet HD 143811 AB b, which was recently discovered using data from the Gemini Planet Imager and Keck NIRC2. A member of the Sco-Cen star-forming region with an age of 13 ± 4 Myr, HD 14…
View article: HD 143811 AB b: A Directly Imaged Planet Orbiting a Spectroscopic Binary in Sco-Cen
HD 143811 AB b: A Directly Imaged Planet Orbiting a Spectroscopic Binary in Sco-Cen Open
We present confirmation of HD 143811 AB b, a substellar companion to spectroscopic binary HD 143811 AB through direct imaging with the Gemini Planet Imager (GPI) and Keck NIRC2. HD 143811 AB was observed as a part of the GPI Exoplanet Surv…
View article: Revised Mass and Orbit of <i>ε</i> Eridani b: A 1 <i>M</i> <sub>Jup</sub> Planet on a Near-circular Orbit
Revised Mass and Orbit of <i>ε</i> Eridani b: A 1 <i>M</i> <sub>Jup</sub> Planet on a Near-circular Orbit Open
The mature Jovian planet ε Eridani b ( ε Eri b) orbits one of the closest Sun-like stars at a moderate separation of 3.5 au, presenting one of the best opportunities to image a true analog to a solar system planet. We perform a thorough jo…
View article: New Orbital Constraints for YSES 1 b and HR 2562 B from High-Precision Astrometry and Planetary Radial Velocities<sup>∗</sup>
New Orbital Constraints for YSES 1 b and HR 2562 B from High-Precision Astrometry and Planetary Radial Velocities<sup>∗</sup> Open
We present new VLTI/GRAVITY astrometry and updated orbit fits for the directly imaged companions YSES 1 b and HR 2562 B, substellar objects straddling the planet–brown-dwarf boundary. Using high-precision astrometry, radial velocity data, …
View article: Characterization of the Host Binary of the Directly Imaged Exoplanet HD 143811 AB b
Characterization of the Host Binary of the Directly Imaged Exoplanet HD 143811 AB b Open
HD~143811~AB is the host star to the directly imaged planet HD~143811~AB~b, which was recently discovered using data from the Gemini Planet Imager and Keck NIRC2. A member of the Sco-Cen star-forming region with an age of $13 \pm 4$ Myr, H…
View article: HD 143811 AB b: A Directly Imaged Planet Orbiting a Spectroscopic Binary in Sco-Cen
HD 143811 AB b: A Directly Imaged Planet Orbiting a Spectroscopic Binary in Sco-Cen Open
We present confirmation of HD 143811 AB b, a substellar companion to spectroscopic binary HD 143811 AB through direct imaging with the Gemini Planet Imager (GPI) and Keck NIRC2. HD 143811 AB was observed as a part of the Gemini Planet Imag…
View article: Requirements for Joint Orbital Characterization of Cold Giants and Habitable Worlds with Habitable Worlds Observatory
Requirements for Joint Orbital Characterization of Cold Giants and Habitable Worlds with Habitable Worlds Observatory Open
We determine optimal requirements for the joint detection of habitable-zone planets and cold giant planets with the Habitable Worlds Observatory (HWO). Analysis of 164 nearby stars shows that a coronagraph outer working angle of 1440 milli…
View article: Apache Point Observatory Follow-up of ACcelerating Candidate ExopLanet Host Stars (APO ACCELS): Ages for 166 Accelerating Stars in the Northern Hemisphere
Apache Point Observatory Follow-up of ACcelerating Candidate ExopLanet Host Stars (APO ACCELS): Ages for 166 Accelerating Stars in the Northern Hemisphere Open
Directly imaged substellar companions with well-constrained ages and masses serve as vital empirical benchmarks for planet formation and evolution models. Potential benchmark companions can be identified from astrometric accelerations of t…
View article: Occurrence Rates of Accreting Companions from a New Method for Computing Emission-line Survey Sensitivity: Application to the H<i>α</i> Giant Accreting Protoplanet Survey
Occurrence Rates of Accreting Companions from a New Method for Computing Emission-line Survey Sensitivity: Application to the H<i>α</i> Giant Accreting Protoplanet Survey Open
A key scientific goal of exoplanet surveys is to characterize the underlying population of planets in the local galaxy. In particular, the properties of accreting proto planets can inform the rates and physical processes of planet formatio…
View article: On the Orbit of the Binary Brown Dwarf Companion GL229 Ba and Bb
On the Orbit of the Binary Brown Dwarf Companion GL229 Ba and Bb Open
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 m…
View article: On the Orbit of the Binary Brown Dwarf Companion GL229 Ba and Bb
On the Orbit of the Binary Brown Dwarf Companion GL229 Ba and Bb Open
The companion GL229B was recently resolved by Xuan et al. (2024) as a tight binary of two brown dwarfs (Ba and Bb) through VLTI-GRAVITY interferometry and VLT-CRIRES+ RV measurements. Here, we present Bayesian models of the interferometric…
View article: Radial Velocity and Astrometric Evidence for a Close Companion to Betelgeuse
Radial Velocity and Astrometric Evidence for a Close Companion to Betelgeuse Open
We examine a century of radial velocity, visual magnitude, and astrometric observations of the nearest red supergiant, Betelgeuse, in order to reexamine the century-old assertion that Betelgeuse might be a spectroscopic binary. These data …
View article: orbitize! v3: Orbit fitting for the High-contrastImaging Community
orbitize! v3: Orbit fitting for the High-contrastImaging Community Open
Instrumentation
View article: orbitize! v3: Orbit fitting for the High-contrast Imaging Community
orbitize! v3: Orbit fitting for the High-contrast Imaging Community Open
orbitize! is a package for Bayesian modeling of the orbital parameters of resolved binary objects from time series measurements. It was developed with the needs of the high-contrast imaging community in mind, and has since also become wide…
View article: Occurrence rates of accreting companions from a new method for computing emission-line survey sensitivity: application to the H-alpha Giant Accreting Protoplanet Survey
Occurrence rates of accreting companions from a new method for computing emission-line survey sensitivity: application to the H-alpha Giant Accreting Protoplanet Survey Open
A key scientific goal of exoplanet surveys is to characterize the underlying population of planets in the local galaxy. In particular, the properties of accreting protoplanets can inform the rates and physical processes of planet formation…
View article: Analyzing the atmospheric dispersion correction of the Gemini Planet Imager: residual dispersion above design requirements
Analyzing the atmospheric dispersion correction of the Gemini Planet Imager: residual dispersion above design requirements Open
The Atmospheric Dispersion Corrector (ADC) of the Gemini Planet Imager (GPI) corrects the chromatic dispersion caused by differential atmospheric refraction (DAR), making it an important optic for exoplanet observation. Despite requiring l…
View article: A uniform analysis of debris discs with the Gemini Planet Imager II: constraints on dust density distribution using empirically informed scattering phase functions
A uniform analysis of debris discs with the Gemini Planet Imager II: constraints on dust density distribution using empirically informed scattering phase functions Open
Spatially resolved images of debris discs are necessary to determine disc morphological properties and the scattering phase function (SPF) thatantifies the brightness of scattered light as a function of phase angle. Current high-contrast i…
View article: Validation of Elemental and Isotopic Abundances in Late-M Spectral Types with the Benchmark HIP 55507 AB System
Validation of Elemental and Isotopic Abundances in Late-M Spectral Types with the Benchmark HIP 55507 AB System Open
M dwarfs are common host stars to exoplanets but often lack atmospheric abundance measurements. Late-M dwarfs are also good analogs to the youngest substellar companions, which share similar T eff ∼ 2300–2800 K. We present atmospheric anal…
View article: A Uniform Analysis of Debris Disks with the Gemini Planet Imager. I. An Empirical Search for Perturbations from Planetary Companions in Polarized Light Images
A Uniform Analysis of Debris Disks with the Gemini Planet Imager. I. An Empirical Search for Perturbations from Planetary Companions in Polarized Light Images Open
The Gemini Planet Imager (GPI) has excelled in imaging debris disks in the near-infrared. The GPI Exoplanet Survey imaged 24 debris disks in polarized H -band light, while other programs observed half of these disks in polarized J and/or K…
View article: A Uniform Analysis of Debris Disks with the Gemini Planet Imager II: Constraints on Dust Density Distribution Using Empirically-Informed Scattering Phase Functions
A Uniform Analysis of Debris Disks with the Gemini Planet Imager II: Constraints on Dust Density Distribution Using Empirically-Informed Scattering Phase Functions Open
Spatially-resolved images of debris disks are necessary to determine disk morphological properties and the scattering phase function (SPF) which quantifies the brightness of scattered light as a function of phase angle. Current high-contra…
View article: Validation of elemental and isotopic abundances in late-M spectral types with the benchmark HIP 55507 AB system
Validation of elemental and isotopic abundances in late-M spectral types with the benchmark HIP 55507 AB system Open
M dwarfs are common host stars to exoplanets but often lack atmospheric abundance measurements. Late-M dwarfs are also good analogs to the youngest substellar companions, which share similar $T_{\rm eff}\sim2300-2800~K$. We present atmosph…
View article: A Uniform Analysis of Debris Disks with the Gemini Planet Imager I: An Empirical Search for Perturbations from Planetary Companions in Polarized Light Images
A Uniform Analysis of Debris Disks with the Gemini Planet Imager I: An Empirical Search for Perturbations from Planetary Companions in Polarized Light Images Open
The Gemini Planet Imager (GPI) has excelled in imaging debris disks in the near-infrared. The GPI Exoplanet Survey (GPIES) imaged twenty-four debris disks in polarized $H$-band light, while other programs observed half of these disks in po…
View article: CD –27°11535: Evidence for a Triple System in the β Pictoris Moving Group
CD –27°11535: Evidence for a Triple System in the β Pictoris Moving Group Open
We present new spatially resolved astrometry and photometry of the CD –27°11535 system, a member of the β Pictoris moving group consisting of two resolved K-type stars on a ∼20 yr orbit. We fit an orbit to relative astrometry measured from…
View article: TESS Hunt for Young and Maturing Exoplanets (THYME): A Planet in the 45 Myr Tucana-Horologium Association
TESS Hunt for Young and Maturing Exoplanets (THYME): A Planet in the 45 Myr Tucana-Horologium Association Open
Young exoplanets are snapshots of the planetary evolution process. Planets that orbit stars in young associations are particularly important because the age of the planetary system is well constrained. We present the discovery of a transit…
View article: Knowledge, attitudes, and practices of pregnant women regarding COVID-19 vaccination in pregnancy in 7 low- and middle-income countries: An observational trial from the Global Network for Women and Children’s Health Research
Knowledge, attitudes, and practices of pregnant women regarding COVID-19 vaccination in pregnancy in 7 low- and middle-income countries: An observational trial from the Global Network for Women and Children’s Health Research Open
Objectives: We sought to determine the knowledge, attitudes and practices of pregnant women regarding COVID-19 vaccination in pregnancy in seven low- and middle-income countries (LMIC). Design: Prospective, observational, population-based …
View article: Detecting Exoplanets Closer to Stars with Moderate Spectral Resolution Integral-field Spectroscopy
Detecting Exoplanets Closer to Stars with Moderate Spectral Resolution Integral-field Spectroscopy Open
While radial velocity surveys have demonstrated that the population of gas giants peaks around 3 au, the most recent high-contrast imaging surveys have only been sensitive to planets beyond ∼10 au. Sensitivity at small angular separations …
View article: Improving MCMC Convergence for Joint Astrometry and Radial Velocity Orbit-fits Through Reparameterization
Improving MCMC Convergence for Joint Astrometry and Radial Velocity Orbit-fits Through Reparameterization Open
The exoplanet orbit-fitting software package orbitize ! was initially designed to fit the orbits of directly imaged planets with relative astrometric measurements using a Markov Chain Monte Carlo (MCMC) algorithm. Since the publication of …
View article: Detecting Exoplanets Closer to Stars with Moderate Spectral Resolution Integral-Field Spectroscopy
Detecting Exoplanets Closer to Stars with Moderate Spectral Resolution Integral-Field Spectroscopy Open
While radial velocity surveys have demonstrated that the population of gas giants peaks around $3~\text{au}$, the most recent high-contrast imaging surveys have only been sensitive to planets beyond $\sim~10~\text{au}$. Sensitivity at smal…
View article: Testing the Interaction between a Substellar Companion and a Debris Disk in the HR 2562 System
Testing the Interaction between a Substellar Companion and a Debris Disk in the HR 2562 System Open
The HR 2562 system is a rare case where a brown dwarf companion resides in a cleared inner hole of a debris disk, offering invaluable opportunities to study the dynamical interaction between a substellar companion and a dusty disk. We pres…
View article: Enabling Exoplanet Demographics Studies with Standardized Exoplanet Survey Meta-Data
Enabling Exoplanet Demographics Studies with Standardized Exoplanet Survey Meta-Data Open
Goal 1 of the National Academies of Science, Engineering and Mathematics Exoplanet Science Strategy is "to understand the formation and evolution of planetary systems as products of the process of star formation, and characterize and expla…