Search Publications

A Census of Star Formation in the Outer Galaxy. II. The GLIMPSE360 Field
DOI: 10.3847/1538-3881/ab99c8 Bibcode: 2020AJ....160...68W

Hora, Joseph L.; Tolls, Volker; Winston, Elaine

We have conducted a study of star formation in the outer Galaxy from 65°< l < 265° in the region observed by the GLIMPSE360 program. This Spitzer warm mission program mapped the plane of the outer Milky Way with IRAC at 3.6 and 4.5 µm. We combine the IRAC, Wide-field Infrared Survey Explorer (WISE), and Two Micron All Sky Survey catalo…

2020 The Astronomical Journal
Gaia 18
Endogenic and Exogenic Contributions to Visible-wavelength Spectra of Europa's Trailing Hemisphere
DOI: 10.3847/1538-3881/abc34c Bibcode: 2020AJ....160..282T

Brown, Michael E.; Hand, Kevin P.; Trumbo, Samantha K.

The composition of Europa's trailing hemisphere reflects the combined influences of endogenous geologic resurfacing and exogenous sulfur radiolysis. Using spatially resolved visible-wavelength spectra of Europa obtained with the Hubble Space Telescope, we map multiple spectral features across the trailing hemisphere and compare their geographies w…

2020 The Astronomical Journal
eHST 18
SCExAO/CHARIS Near-infrared Integral Field Spectroscopy of the HD 15115 Debris Disk
DOI: 10.3847/1538-3881/ababa6 Bibcode: 2020AJ....160..163L

Henning, Thomas; Currie, Thayne; Schneider, Glenn +23 more

We present new, near-infrared (1.1-2.4 µm) high-contrast imaging of the debris disk around HD 15115 with the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system coupled with the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS). The SCExAO/CHARIS resolves the disk down to ρ ∼ 0"2 (rproj ∼ 10 au), a facto…

2020 The Astronomical Journal
Gaia eHST 18
It Takes Two Planets in Resonance to Tango around K2-146
DOI: 10.3847/1538-3881/ab66c9 Bibcode: 2020AJ....159..120L

Cochran, William D.; Endl, Michael; Mahadevan, Suvrath +51 more

K2-146 is a cool, 0.358 ${M}_{\odot }$ dwarf that was found to host a mini-Neptune with a 2.67 day period. The planet exhibited strong transit timing variations (TTVs) of greater than 30 minutes, indicative of the presence of an additional object in the system. Here we report the discovery of the previously undetected outer planet in the system, K…

2020 The Astronomical Journal
Gaia 18
A Study of the Blue Straggler Population of the Old Open Cluster Collinder 261
DOI: 10.3847/1538-3881/ab5f0b Bibcode: 2020AJ....159...59R

Monaco, L.; Beccari, G.; Villanova, S. +4 more

Blue stragglers (BSs) are stars located in an unexpected region of the color-magnitude diagram (CMD) of a stellar population, as they appear bluer and more luminous than the stars in the turn-off region. They are ubiquitous, since they have been found among Milky Way field stars, in open and globular clusters, and also in other galaxies of the Loc…

2020 The Astronomical Journal
Gaia 17
OGLE-2015-BLG-1771Lb: A Microlens Planet Orbiting an Ultracool Dwarf?
DOI: 10.3847/1538-3881/ab6f6d Bibcode: 2020AJ....159..116Z

Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +31 more

We report the discovery and the analysis of the short ( ${t}_{{\rm{E}}}\lt 5$ days) planetary microlensing event, OGLE-2015-BLG-1771. The event was discovered by the Optical Gravitational Lensing Experiment, and the planetary anomaly (at I ∼ 19) was captured by The Korea Microlensing Telescope Network. The event has three surviving planetary model…

2020 The Astronomical Journal
eHST 17
ALMA 0.88 mm Survey of Disks around Planetary-mass Companions
DOI: 10.3847/1538-3881/ab818c Bibcode: 2020AJ....159..229W

Herczeg, Gregory J.; Wilner, David J.; Kraus, Adam L. +6 more

Characterizing the physical properties and compositions of circumplanetary disks can provide important insights into the formation of giant planets and satellites. We report Atacama Large Millimeter/submillimeter Array 0.88 mm (Band 7) continuum observations of six planetary-mass (10-20 MJup) companions: CT Cha b, 1RXS 1609 b, ROXs 12 b…

2020 The Astronomical Journal
Gaia 17
TOI 694b and TIC 220568520b: Two Low-mass Companions near the Hydrogen-burning Mass Limit Orbiting Sun-like Stars
DOI: 10.3847/1538-3881/aba526 Bibcode: 2020AJ....160..133M

Henning, Thomas; Butler, R. Paul; Latham, David W. +40 more

We report the discovery of TOI 694 b and TIC 220568520 b, two low-mass stellar companions in eccentric orbits around metal-rich Sun-like stars, first detected by the Transiting Exoplanet Survey Satellite (TESS). TOI 694 b has an orbital period of 48.05131 ± 0.00019 days and eccentricity of 0.51946 ± 0.00081, and we derive a mass of 89.0 ± 5.3 ${M}…

2020 The Astronomical Journal
Gaia 17
K2-19b and c are in a 3:2 Commensurability but out of Resonance: A Challenge to Planet Assembly by Convergent Migration
DOI: 10.3847/1538-3881/ab5220 Bibcode: 2020AJ....159....2P

Espinoza, Néstor; Bayliss, Daniel; Fulton, Benjamin J. +11 more

K2-19b and c were among the first planets discovered by NASA’s K2 mission and together stand in stark contrast with the physical and orbital properties of the solar system planets. The planets are between the size of Uranus and Saturn at 7.0 ± 0.2 {R}\oplus and 4.1 ± 0.2 {R}\oplus , respectively, and reside a mere 0.1% outsi…

2020 The Astronomical Journal
Gaia 17
Follow-up Studies of Five Cataclysmic Variable Candidates Discovered by LAMOST
DOI: 10.3847/1538-3881/aba7c7 Bibcode: 2020AJ....160..151T

Thorstensen, John R.

We report follow-up observations of five cataclysmic variable candidates from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) published by Hou et al. LAMOST J024048.51+195226.9 is the most unusual of the five; an early-M type secondary star contributes strongly to its spectrum, and its spectral and photometric behavior are s…

2020 The Astronomical Journal
Gaia 17