Search Publications
The Solar Neighborhood. XXXX. Parallax Results from the CTIOPI 0.9 m Program: New Young Stars Near the Sun
Henry, Todd J.; Winters, Jennifer G.; Jao, Wei-Chun +6 more
As a step toward completing and characterizing the census of the solar neighborhood, we present astrometric, photometric, and spectroscopic observations of 32 systems observed with the Cerro Tololo Inter-American Observatory 0.9 m and 1.5 m telescopes. Astrometry from the 0.9 m indicates that among the 17 systems that had no previous published tri…
New Low-mass Stars in the 25 Orionis Stellar Group and Orion OB1a Sub-association from SDSS-III/BOSS Spectroscopy
Stassun, Keivan G.; Petr-Gotzens, Monika G.; Suárez, Genaro +6 more
The Orion OB1a sub-association is a rich low-mass star (LMS) region. Previous spectroscopic studies have confirmed 160 LMSs in the 25 Orionis stellar group (25 Ori), which is the most prominent overdensity of Orion OB1a. Nonetheless, the current census of the 25 Ori members is estimated to be lower than 50% complete, leaving a large number of memb…
Galaxy Populations in Massive z = 0.2-0.9 Clusters. I. Analysis of Spectroscopy
Jørgensen, Inger; Chiboucas, Kristin; Takamiya, Marianne +3 more
We present an analysis of stellar populations in passive galaxies in seven massive X-ray clusters at z = 0.19-0.89. Based on absorption-line strengths measured from our high signal-to-noise spectra, the data support primarily passive evolution of the galaxies. We use the scaling relations between velocity dispersions and the absorption-line streng…
Absolute-magnitude Calibration for W UMa-type Systems Based on Gaia Data
Rucinski, Slavek M.; Mateo, Nicole M.
Tycho-Gaia Astrometric Solution (TGAS) parallax data are used to determine absolute magnitudes M V for 318 W UMa-type (EW) contact binary stars. A very steep (slope ≃ -9), single-parameter ({log}P), linear calibration can be used to predict M V to about 0.1-0.3 mag over the whole range of accessible orbital period, 0.22&l…
K2-60b and K2-107b. A Sub-Jovian and a Jovian Planet from the K2 Mission
Cochran, William D.; Endl, Michael; Gandolfi, Davide +20 more
We report the characterization and independent detection of K2-60b, as well as the detection and characterization of K2-107b, two transiting hot gaseous planets from the K2 space mission. We confirm the planetary nature of the two systems and determine their fundamental parameters combining the K2 time-series data with FIES@NOT and HARPS-N@TNG spe…
Imaging Observations of the Hydrogen Coma of Comet 67P/Churyumov-Gerasimenko in 2015 September by the PROCYON/LAICA
Combi, Michael R.; Shinnaka, Yoshiharu; Fougere, Nicolas +8 more
The water production rate of a comet is one of the fundamental parameters necessary to understand cometary activity when a comet approaches the Sun within 2.5 au, because water is the most abundant icy material in the cometary nucleus. Wide-field imaging observations of the hydrogen Lyα emission in comet 67P/Churyumov-Gerasimenko were performed by…
The Unusual Apparition of Comet 252P/2000 G1 (LINEAR) and Comparison with Comet P/2016 BA14 (PanSTARRS)
Samarasinha, Nalin H.; Tholen, David J.; Li, Jian-Yang +7 more
We imaged Comet 252P/2000 G1 (LINEAR; hereafter 252P) with the Hubble Space Telescope and both 252P and P/2016 BA14 (PanSTARRS; hereafter BA14) with the Discovery Channel Telescope in 2016 March and April, surrounding its close encounter to Earth. The r‧-band Afρ of 252P in a 0.″2-radius aperture were 16.8 ± 0.3 and 57 ± 1 cm…
The Late-Type Extension to MoVeRS (LaTE-MoVeRS): Proper Motion Verified Low-mass Stars and Brown Dwarfs from SDSS, 2MASS, and WISE
Burgasser, Adam J.; Schmidt, Sarah J.; Theissen, Christopher A. +2 more
We present the Late-Type Extension to the Motion Verified Red Stars (LaTE-MoVeRS) catalog, containing 46,463 photometric late-type (>M5) dwarfs within the Sloan Digital Sky Survey (SDSS) footprint. Proper motions were computed for objects combining astrometry from the SDSS Data Release 12 (DR12), the Two-micron All-Sky Survey (2MASS) Point Sour…
Exploratory Spectroscopy of Magnetic Cataclysmic Variables Candidates and Other Variable Objects
Oliveira, A. S.; Rodrigues, C. V.; Palhares, M. S. +5 more
The increasing number of synoptic surveys made by small robotic telescopes, such as the photometric Catalina Real-Time Transient Survey (CRTS), provides a unique opportunity to discover variable sources and improves the statistical samples of such classes of objects. Our goal is the discovery of magnetic Cataclysmic Variables (mCVs). These are rar…
The Not So Simple Globular Cluster ω Cen. I. Spatial Distribution of the Multiple Stellar Populations
Rest, A.; Zenteno, A.; Saha, A. +8 more
We present a multi-band photometric catalog of ≈1.7 million cluster members for a field of view of ≈2° × 2° across ω Cen. Photometry is based on images collected with the Dark Energy Camera on the 4 m Blanco telescope and the Advanced Camera for Surveys on the Hubble Space Telescope. The unprecedented photometric accuracy and field coverage allowe…