Search Publications
A 3D Drizzle Algorithm for JWST and Practical Application to the MIRI Medium Resolution Spectrometer
Law, David R.; Vandenbussche, Bart; Patapis, Polychronis +4 more
We describe an algorithm for application of the classic "drizzle" technique to produce 3D spectral cubes using data obtained from the slicer-type integral field unit (IFU) spectrometers on board the James Webb Space Telescope. This algorithm relies upon the computation of overlapping volume elements (composed of two spatial dimensions and one spec…
A Noninteracting Galactic Black Hole Candidate in a Binary System with a Main-sequence Star
Dalba, Paul A.; Geha, Marla; Chang, Philip +10 more
We describe the discovery of a solar neighborhood (d = 468 pc) binary system with a main-sequence sunlike star and a massive noninteracting black hole candidate. The spectral energy distribution of the visible star is described by a single stellar model. We derive stellar parameters from a high signal-to-noise Magellan/MIKE spectrum, classifying t…
Free-floating Planet Mass Function from MOA-II 9 yr Survey toward the Galactic Bulge
Fukui, Akihiko; Sumi, Takahiro; Bond, Ian A. +25 more
We present the first measurement of the mass function of free-floating planets (FFPs), or very wide orbit planets down to an Earth mass, from the MOA-II microlensing survey in 2006-2014. Six events are likely to be due to planets with Einstein radius crossing times t E < 0.5 days, and the shortest has t E = 0.057 ± 0.016 d…
Detection of Atmospheric Escape from Four Young Mini-Neptunes
Knutson, Heather A.; Ricker, George R.; Dai, Fei +5 more
We use Keck/NIRSPEC to survey a sample of of young (<1 Gyr), short-period mini-Neptunes orbiting nearby K dwarfs to measure their mass loss via the metastable helium line. We detect helium absorption from all four of the targets in our initial sample. The first detection, around TOI 560b, was announced in a previous paper. We now announce three…
Occurrence Rate of Hot Jupiters Around Early-type M Dwarfs Based on Transiting Exoplanet Survey Satellite Data
Latham, David W.; Stassun, Keivan G.; Collins, Karen A. +26 more
We present an estimate of the occurrence rate of hot Jupiters (7 R ⊕ ≤ R p ≤ 2 R J, 0.8 ≤ P b ≤ 10 days) around early-type M dwarfs based on stars observed by the Transiting Exoplanet Survey Satellite (TESS) during its primary mission. We adopt stellar parameters from the TESS Input Catalog and const…
Evidence for Hidden Nearby Companions to Hot Jupiters
Rice, Malena; Wang, Songhu; Wu, Dong-Hong
The first discovered extrasolar worlds-giant, "hot Jupiter" planets on short-period orbits-came as a surprise to solar system-centric models of planet formation, prompting the development of new theories for planetary system evolution. The near absence of observed nearby planetary companions to hot Jupiters has been widely quoted as evidence in su…
TOI-1136 is a Young, Coplanar, Aligned Planetary System in a Pristine Resonant Chain
Terentev, Ivan A.; Batalha, Natalie M.; Bieryla, Allyson +60 more
Convergent disk migration has long been suspected to be responsible for forming planetary systems with a chain of mean-motion resonances (MMRs). Dynamical evolution over time could disrupt the delicate resonant configuration. We present TOI-1136, a 700 ± 150 Myr old G star hosting at least six transiting planets between ~2 and 5 R ⊕. Th…
TOI-5205b: A Short-period Jovian Planet Transiting a Mid-M Dwarf
Kobulnicky, Henry A.; Cochran, William D.; Mahadevan, Suvrath +27 more
We present the discovery of TOI-5205b, a transiting Jovian planet orbiting a solar metallicity M4V star, which was discovered using Transiting Exoplanet Survey Satellite photometry and then confirmed using a combination of precise radial velocities, ground-based photometry, spectra, and speckle imaging. TOI-5205b has one of the highest mass ratios…
Detailed Chemical Abundances of Stars in the Outskirts of the Tucana II Ultrafaint Dwarf Galaxy
Jerjen, Helmut; Frebel, Anna; Simon, Joshua D. +6 more
We present chemical abundances and velocities of five stars between 0.3 and 1.1 kpc from the center of the Tucana II ultrafaint dwarf galaxy (UFD) from high-resolution Magellan/MIKE spectroscopy. We find that every star is deficient in metals (-3.6 < [Fe/H] < -1.9) and in neutron-capture elements as is characteristic of UFD stars, unambiguou…
ELemental abundances of Planets and brown dwarfs Imaged around Stars (ELPIS). I. Potential Metal Enrichment of the Exoplanet AF Lep b and a Novel Retrieval Approach for Cloudy Self-luminous Atmospheres
Fortney, Jonathan J.; Carter, Aarynn L.; Skemer, Andrew +10 more
AF Lep A+b is a remarkable planetary system hosting a gas-giant planet that has the lowest dynamical mass among directly imaged exoplanets. We present an in-depth analysis of the atmospheric composition of the star and planet to probe the planet's formation pathway. Based on new high-resolution spectroscopy of AF Lep A, we measure a uniform set of…