Search Publications
Searching for Black Hole Candidates by LAMOST and ASAS-SN
Liu, Jifeng; Bai, Yu; Gu, Wei-Min +13 more
Most dynamically confirmed stellar-mass black holes (BHs) and their candidates were originally selected from X-ray outbursts. In the present work, we search for BH candidates in the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey using the spectra along with photometry from the All Sky Automated Survey for SuperNovae (ASA…
Extended X-Ray Study of M49: The Frontier of the Virgo Cluster
Mernier, F.; Churazov, E.; Maccarone, T. J. +10 more
The M49 group, residing outside the virial radius of the Virgo cluster, is falling onto the cluster from the south. We report results from deep XMM-Newton mosaic observations of M49. Its hot gas temperature is 0.8 keV at the group center and rises to 1.5 keV beyond the brightest group galaxy (BGG). The group gas extends to radii of ∼300 kpc to the…
An 11 Earth-mass, Long-period Sub-Neptune Orbiting a Sun-like Star
López-Morales, Mercedes; Latham, David W.; Mayo, Andrew W. +27 more
Although several thousands of exoplanets have now been detected and characterized, observational biases have led to a paucity of long-period, low-mass exoplanets with measured masses and a corresponding lag in our understanding of such planets. In this paper we report the mass estimation and characterization of the long-period exoplanet Kepler-538…
Speckle Observations and Orbits of Multiple Stars
Torres, Guillermo; Latham, David W.; Tokovinin, Andrei +2 more
We report results of speckle-interferometric monitoring of visual hierarchical systems using the newly commissioned instrument NN-EXPLORE Exoplanet and Stellar Speckle Imager at the 3.5 m WIYN telescope. During one year, 390 measurements of 129 resolved subsystems were made, while some targets were unresolved. Using our astrometry and archival dat…
Infrared K-band Photometry of Field RR Lyrae Variable Stars
Layden, Andrew C.; Chaboyer, Brian; Tiede, Glenn P. +2 more
We present multi-epoch infrared photometry in the K s -band for 74 bright RR Lyrae variable stars tied directly to the Two-Micron All-Sky Survey (2MASS) photometric system. We systematize additional K-band photometry from the literature to the 2MASS system and combine it to obtain photometry for 146 RR Lyrae stars on a consistent, mode…
Spectroscopic Follow-up of Discoveries from the NEOWISE Proper Motion Survey
Cushing, Michael C.; Kirkpatrick, J. Davy; Burgasser, Adam J. +2 more
We present low-resolution near-infrared spectra of discoveries from an all-sky proper motion search conducted using multi-epoch data from the Wide-field Infrared Survey Explorer. Using the data from NEOWISE, along with the AllWISE catalog, Schneider et al. conducted an all-sky proper motion survey to search for nearby objects with high proper moti…
Spitzer Transit Follow-up of Planet Candidates from the K2 Mission
Gorjian, Varoujan; Tamura, Motohide; Knutson, Heather A. +21 more
We present precision 4.5 µ {{m}} Spitzer transit photometry of eight planet candidates discovered by the K2 mission: K2-52 b, K2-53 b, EPIC 205084841.01, K2-289 b, K2-174 b, K2-87 b, K2-90 b, and K2-124 b. The sample includes four sub-Neptunes and two sub-Saturns, with radii between 2.6 and 18 {R}\oplus and equilibrium temperatur…
Spitzer Parallax of OGLE-2018-BLG-0596: A Low-mass-ratio Planet around an M Dwarf
Stassun, Keivan G.; Han, Cheongho; Udalski, Andrzej +73 more
We report the discovery of a Spitzer microlensing planet OGLE-2018-BLG-0596Lb, with preferred planet-host mass ratio q ∼ 2 × 10-4. The planetary signal, which is characterized by a short (∼1 day) “bump” on the rising side of the lensing light curve, was densely covered by ground-based surveys. We find that the signal can be explained by…
Small Planets in the Galactic Context: Host Star Kinematics, Iron, and Alpha-element Enhancement
Bashi, Dolev; Zucker, Shay
We explored the occurrence rate of small close-in planets among Kepler target stars as a function of the iron abundance and the stellar total velocity {V}tot}. We estimated the occurrence rate of those planets by combining information from the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) and the California-Kepler S…
Phase Curves from the Kuiper Belt: Photometric Properties of Distant Kuiper Belt Objects Observed by New Horizons
Buratti, Bonnie J.; Singer, Kelsi N.; Stern, S. Alan +17 more
Prior to its close encounter with the Kuiper Belt object (KBO) (486958) 2014 MU69 on 2019 January 1, NASA’s New Horizons spacecraft observed other KBOs from distances greater than 0.1 au at solar phase angles far larger than those attainable from Earth. The expanded range in phase angle afforded by these distant KBO (DKBO) observations …