Search Publications
TESS-Gaia Light Curve: A PSF-based TESS FFI Light-curve Product
Brandt, Timothy D.; Han, Te
The Transiting Exoplanet Survey Satellite (TESS) is continuing its second extended mission after 55 sectors of observations. TESS publishes full-frame images (FFIs) at a cadence of 1800, 600, or 200 s, allowing light curves to be extracted for stars beyond a limited number of pre-selected stars. Simulations show that thousands of exoplanets, eclip…
Localizing Sources of Variability in Crowded TESS Photometry
Bell, Keaton J.; Higgins, Michael E.
The Transiting Exoplanet Survey Satellite (TESS) has an exceptionally large plate scale of 21″ px-1, causing most TESS light curves to record the blended light of multiple stars. This creates a danger of misattributing variability observed by TESS to the wrong source, which would invalidate any analysis. We developed a method that can l…
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…
Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II
Klessen, Ralf S.; Johnson, Christian I.; Mateo, Mario +9 more
The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r-process event. The r-process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member st…
Terrestrial- and Neptune-mass Free-Floating Planet Candidates from the MOA-II 9 yr Galactic Bulge Survey
Udalski, Andrzej; Mróz, Przemek; Fukui, Akihiko +28 more
We report the discoveries of low-mass free-floating planet (FFP) candidates from the analysis of 2006-2014 MOA-II Galactic bulge survey data. In this data set, we found 6111 microlensing candidates and identified a statistical sample consisting of 3535 high-quality single-lens events with Einstein radius crossing times in the range 0.057 < t
Assessing the C/O Ratio Formation Diagnostic: A Potential Trend with Companion Mass
Macintosh, Bruce; Perrin, Marshall D.; Barman, Travis S. +6 more
The carbon-to-oxygen (C/O) ratio in an exoplanet atmosphere has been suggested as a potential diagnostic of planet formation. Now that a number of exoplanets have measured C/O ratios, it is possible to examine this diagnostic at a population level. Here, we present an analysis of currently measured C/O ratios of directly imaged and transit/eclipse…
Bioverse: A Comprehensive Assessment of the Capabilities of Extremely Large Telescopes to Probe Earth-like O2 Levels in Nearby Transiting Habitable-zone Exoplanets
Pascucci, Ilaria; López-Morales, Mercedes; Apai, Dániel +2 more
Molecular oxygen is a strong indicator of life on Earth and may indicate biological processes on exoplanets too. Recent studies proposed that Earth-like O2 levels might be detectable on nearby exoplanets using high-resolution spectrographs on future extremely large telescopes (ELTs). However, these studies did not consider constraints l…
TESS Hunt for Young and Maturing Exoplanets (THYME). IX. A 27 Myr Extended Population of Lower Centaurus Crux with a Transiting Two-planet System
Vanderburg, Andrew; Latham, David W.; Quinn, Samuel N. +35 more
We report the discovery and characterization of a nearby (~85 pc), older (27 ± 3 Myr), distributed stellar population near Lower Centaurus Crux (LCC), initially identified by searching for stars comoving with a candidate transiting planet from TESS (HD 109833; TOI 1097). We determine the association membership using Gaia kinematics, color-magnitud…
The Absolute Age of M92
Chaboyer, Brian; Boylan-Kolchin, Michael; Weisz, Daniel +3 more
The absolute age of a simple stellar population is of fundamental interest for a wide range of applications but is difficult to measure in practice, as it requires an understanding of the uncertainties in a variety of stellar evolution processes as well as the uncertainty in the distance, reddening, and composition. As a result, most studies focus…
A Unified Treatment of Kepler Occurrence to Trace Planet Evolution. I. Methodology
Dattilo, Anne; Batalha, Natalie M.; Bryson, Steve
We present Kepler exoplanet occurrence rates for planets between 0.5 and 16 R ⊕ and between 1 and 400 days. To measure occurrence, we use a nonparametric method via a kernel density estimator and use bootstrap random sampling for uncertainty estimation. We use a full characterization of completeness and reliability measurements from the…