Search Publications
SCExAO/CHARIS Near-infrared Integral Field Spectroscopy of the HD 15115 Debris Disk
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…
It Takes Two Planets in Resonance to Tango around K2-146
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…
A Study of the Blue Straggler Population of the Old Open Cluster Collinder 261
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…
OGLE-2015-BLG-1771Lb: A Microlens Planet Orbiting an Ultracool Dwarf?
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…
ALMA 0.88 mm Survey of Disks around Planetary-mass Companions
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…
TOI 694b and TIC 220568520b: Two Low-mass Companions near the Hydrogen-burning Mass Limit Orbiting Sun-like Stars
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}…
K2-19b and c are in a 3:2 Commensurability but out of Resonance: A Challenge to Planet Assembly by Convergent Migration
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…
Follow-up Studies of Five Cataclysmic Variable Candidates Discovered by LAMOST
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…
Radial Star Formation Histories in 32 Nearby Galaxies
Kobulnicky, Henry A.; Dale, Daniel A.; Cox, Isaiah S. +10 more
The spatially resolved star formation histories are studied for 32 normal star-forming galaxies drawn from the Spitzer Extended Disk Galaxy Exploration Science survey. At surface brightness sensitivities fainter than 28 mag arcsec-2, the new optical photometry is deep enough to complement archival ultraviolet and infrared imaging and to…
Near-infrared Imaging of a Spiral in the CQ Tau Disk
Currie, Thayne; Dong, Ruobing; Kwon, Jungmi +28 more
We present L'-band Keck/NIRC2 imaging and H-band Subaru/AO188+HiCIAO polarimetric observations of the CQ Tau disk with a new spiral arm. Apart from the spiral feature, our observations could not detect any companion candidates. We traced the spiral feature from the r2-scaled High-Contrast Coronographic Imager for Adaptive Optics (HiCIAO…