Search Publications
A Sub-2% Distance to M31 from Photometrically Homogeneous Near-infrared Cepheid Period-Luminosity Relations Measured with the Hubble Space Telescope
Casertano, Stefano; Li, Siyang; Riess, Adam G. +3 more
We present period-luminosity relations (PLRs) for 55 Cepheids in M31 with periods ranging from 4 to 78 days observed with the Hubble Space Telescope using the same three-band photometric system recently used to calibrate their luminosities. Images were taken with the Wide Field Camera 3 in two optical filters (F555W and F814W) and one near-infrare…
Hubble Space Telescope Observations of Two Faint Dwarf Satellites of Nearby LMC Analogs from MADCASH
Forbes, Duncan A.; Romanowsky, Aaron J.; Strader, Jay +11 more
We present a deep Hubble Space Telescope (HST) imaging study of two dwarf galaxies in the halos of Local Volume Large Magellanic Cloud (LMC) analogs. These dwarfs were discovered as part of our Subaru+Hyper Suprime-Cam MADCASH survey: MADCASH-1 is a satellite of NGC 2403 (D ∼ 3.2 Mpc), and MADCASH-2 is a previously unknown dwarf galaxy near NGC 42…
On the Correlation between Hot Jupiters and Stellar Clustering: High-eccentricity Migration Induced by Stellar Flybys
Rodet, Laetitia; Lai, Dong; Su, Yubo
A recent observational study suggests that the occurrence of hot Jupiters (HJs) around solar-type stars is correlated with stellar clustering. We study a new scenario for HJ formation, called "Flyby Induced High-e Migration," that may help explain this correlation. In this scenario, stellar flybys excite the eccentricity and inclination of an oute…
Quantifying Non-parametric Structure of High-redshift Galaxies with Deep Learning
Bamford, S. P.; Conselice, C. J.; Ferrari, F. +2 more
At high redshift, due to both observational limitations and the variety of galaxy morphologies in the early universe, measuring galaxy structure can be challenging. Non-parametric measurements such as the CAS system have thus become an important tool due to both their model-independent nature and their utility as a straightforward computational pr…
A Census of Blue Stragglers in Gaia DR2 Open Clusters as a Test of Population Synthesis and Mass Transfer Physics
Leiner, Emily M.; Geller, Aaron
We use photometry and proper motions from Gaia DR2 to determine the blue straggler star (BSS) populations of 16 old (1-10 Gyr), nearby (d < 3500 pc) open clusters. We find that the fractional number of BSS compared to red giant branch stars increases with age, starting near zero at 1 Gyr and flattening to ∼0.35 by 4 Gyr. Fitting stellar evoluti…
A Parametric Galactic Model toward the Galactic Bulge Based on Gaia and Microlensing Data
Bennett, David P.; Koshimoto, Naoki; Baba, Junichi
We developed a parametric Galactic model toward the Galactic bulge by fitting to spatial distributions of the Gaia DR2 disk velocity, VVV proper motion, BRAVA radial velocity, OGLE-III red clump star count, and OGLE-IV star count and microlens rate, optimized for use in microlensing studies. We include the asymmetric drift of Galactic disk stars a…
Evolution of the Thermodynamic Properties of Clusters of Galaxies out to Redshift of 1.8
Mahler, Guillaume; Kraft, Ralph; Khullar, Gourav +11 more
The thermodynamic properties of the hot plasma in galaxy clusters retain information on the processes leading to the formation and evolution of the gas in their deep, dark matter potential wells. These processes are dictated not only by gravity but also by gas physics, e.g., active galactic nucleus feedback and turbulence. In this work, we study t…
The Mass-Metallicity Relation at z 1-2 and Its Dependence on the Star Formation Rate
Papovich, Casey; Barro, Guillermo; Martin, Crystal L. +24 more
We present a new measurement of the gas-phase mass-metallicity relation (MZR) and its dependence on star formation rates (SFRs) at 1.3 < z < 2.3. Our sample comprises 1056 galaxies with a mean redshift of z = 1.9, identified from the Hubble Space Telescope Wide Field Camera 3 (WFC3) grism spectroscopy in the Cosmic Assembly Near-infrared Dee…
Measuring and Replicating the 1-20 µm Energy Distributions of the Coldest Brown Dwarfs: Rotating, Turbulent, and Nonadiabatic Atmospheres
Marley, Mark; Dupuy, Trent J.; Caselden, Dan +7 more
Cold, low-mass, field brown dwarfs are important for constraining the terminus of the stellar mass function, and also for optimizing atmospheric studies of exoplanets. In 2020 new model grids for such objects were made available: Sonora-Bobcat and ATMO 2020. Also, new candidate cold brown dwarfs were announced, and new spectroscopic observations a…
Threaded-field-line Model for the Low Solar Corona Powered by the Alfvén Wave Turbulence
Jin, Meng; Sokolov, Igor V.; Gombosi, Tamas I. +6 more
We present an updated global model of the solar corona, including the transition region. We simulate the realistic three-dimensional (3D) magnetic field using the data from the photospheric magnetic field measurements and assume the magnetohydrodynamic (MHD) Alfvén wave turbulence and its nonlinear dissipation to be the only source for heating the…