Search Publications
WISE 2150-7520AB: A Very Low-mass, Wide Comoving Brown Dwarf System Discovered through the Citizen Science Project Backyard Worlds: Planet 9
Gonzales, Eileen C.; Meisner, Aaron M.; Burgasser, Adam J. +10 more
We report the discovery of WISE 2150-7520AB (W2150AB): a widely separated (∼341 au) very low-mass L1 + T8 co-moving system. The system consists of the previously known L1 primary 2MASS J21501592-7520367 and a newly discovered T8 secondary found at position 21:50:18.99-75:20:54.6 (MJD = 57947) using Wide-field Infrared Survey Explorer data via the …
The Evolution of the Inner Regions of Protoplanetary Disks
Calvet, Nuria; Lizano, Susana; Miller, Christopher J. +6 more
We present a study of the evolution of the inner few astronomical units of protoplanetary disks around low-mass stars. We consider nearby stellar groups with ages spanning from 1 to 11 Myr, distributed into four age bins. Combining PANSTARSS photometry with spectral types, we derive the reddening consistently for each star, which we use (1) to mea…
Solar Flare Arcade Modeling: Bridging the Gap from 1D to 3D Simulations of Optically Thin Radiation
Polito, Vanessa; Kerr, Graham S.; Allred, Joel C.
Solar flares are 3D phenomena, but modeling a flare in 3D, including many of the important processes in the chromosphere, is a computational challenge. Accurately modeling the chromosphere is important, even if the transition region and corona are the areas of interest, due to the flow of energy, mass, and radiation through the interconnected laye…
A Word to the WISE: Confusion is Unavoidable for WISE-selected Infrared Excesses
Debes, John H.; Gentile Fusillo, Nicola Pietro; Farihi, Jay +1 more
Stars with excess infrared radiation from circumstellar dust are invaluable for studies of exoplanetary systems, informing our understanding of processes of planet formation and destruction alike. All-sky photometric surveys have made the identification of dusty infrared excess candidates trivial, however, samples that rely on data from Wise Infra…
Discovery of a Large Population of Nitrogen-enhanced Stars in the Magellanic Clouds
Beers, Timothy C.; Placco, Vinicius M.; Minniti, Dante +7 more
We report the APOGEE-2S+ discovery of a unique collection of nitrogen-enhanced mildly metal-poor giant stars, peaking at [Fe/H] ∼ -0.89 with no carbon enrichment, toward the Small and Large Magellanic Clouds (SMC and LMC), with abundances of light- (C, N), odd-Z (Al, K), and α-elements (O, Mg, Si) that are typically found in Galactic globular clus…
Fast Outflows in Hot Dust-obscured Galaxies Detected with Keck/NIRES
Tsai, Chao-Wei; Moon, Dae-Sik; Jun, Hyunsung D. +10 more
We present rest-frame optical spectroscopic observations of 24 Hot Dust-Obscured Galaxies (Hot DOGs) at redshifts 1.7-4.6 with KECK/NIRES. Our targets are selected, based on their extreme red colors, to be the highest-luminosity sources from the WISE infrared survey. In 20 sources with well-detected emission, we fit the key [O III], Hβ, Hα, [N II]…
Real-time Flare Prediction Based on Distinctions between Flaring and Non-flaring Active Region Spectra
Kleint, Lucia; Panos, Brandon
With machine learning entering into the awareness of the heliophysics community, solar flare prediction has become a topic of increased interest. Although machine-learning models have advanced with each successive publication, the input data has remained largely fixed on magnetic features. Despite this increased model complexity, results seem to i…
The R-process Alliance: The Peculiar Chemical Abundance Pattern of RAVE J183013.5-455510
Whitten, Devin D.; Beers, Timothy C.; Placco, Vinicius M. +14 more
We report on the spectroscopic analysis of RAVE J183013.5-455510, an extremely metal-poor star, highly enhanced in CNO, and with discernible contributions from the rapid neutron-capture process. There is no evidence of binarity for this object. At $[\mathrm{Fe}/{\rm{H}}]$ = -3.57, this star has one of the lowest metallicities currently observed, w…
The Fifth Candidate for an Intermediate-mass Black Hole in the Galactic Center
Oka, Tomoharu; Tsujimoto, Shiho; Iwata, Yuhei +2 more
We report the results of high-resolution molecular line observations of the high-velocity compact cloud HCN-0.085-0.094 with the Atacama Large Millimeter/submillimeter Array. The HCN J = 4-3, HCO+ J = 4-3, and CS J = 7-6 line images reveal that HCN-0.085-0.094 consists mainly of three small clumps with extremely broad velocity widths. E…
Broadband Selection, Spectroscopic Identification, and Physical Properties of a Population of Extreme Emission-line Galaxies at 3 < z < 3.7
Harikane, Yuichi; Shibuya, Takatoshi; Suzuki, Tomoko L. +7 more
We present the selection, spectroscopic identification, and physical properties of extreme emission-line galaxies (EELGs) at 3 < z < 3.7, aiming at studying physical properties of an analog population of star-forming galaxies (SFGs) at the epoch of reionization. The sample is selected based on the excess in the observed Ks broadband flux rel…