Search Publications
WISE J072003.20-084651.2B is a Massive T Dwarf
Shappee, B. J.; Dupuy, Trent J.; Mann, Andrew W. +21 more
We present individual dynamical masses for the nearby M9.5+T5.5 binary WISE J072003.20-084651.2AB, a.k.a. Scholz’s star. Combining high-precision Canada-France-Hawaii Telescope/WIRCam photocenter astrometry and Keck adaptive optics resolved imaging, we measure the first high-quality parallactic distance ({6.80}-0.06+0.05 pc) …
Col-OSSOS: Color and Inclination Are Correlated throughout the Kuiper Belt
Wang, Shiang-Yu; Marsset, Michaël; Fraser, Wesley C. +12 more
Both physical and dynamical properties must be considered to constrain the origins of the dynamically excited distant solar system populations. We present high-precision (g-r) colors for 25 small (H r > 5) dynamically excited trans-Neptunian objects (TNOs) and centaurs acquired as part of the Colours of the Outer Solar System Origins…
OGLE-2018-BLG-1011Lb,c: Microlensing Planetary System with Two Giant Planets Orbiting a Low-mass Star
Stassun, Keivan G.; Han, Cheongho; Udalski, Andrzej +79 more
We report a multiplanetary system found from the analysis of microlensing event OGLE-2018-BLG-1011, for which the light curve exhibits a double-bump anomaly around the peak. We find that the anomaly cannot be fully explained by the binary-lens or binary-source interpretations and its description requires the introduction of an additional lens comp…
Constraints on the Occurrence and Distribution of 1-20 M Jup Companions to Stars at Separations of 5-5000 au from a Compilation of Direct Imaging Surveys
Gagné, Jonathan; Delorme, Philippe; Lafrenière, David +4 more
We present the first statistical analysis of exoplanet direct imaging surveys combining adaptive optics (AO) imaging at small separations with deep seeing-limited observations at large separations allowing us to study the entire orbital separation domain from 5 to 5000 au simultaneously. Our sample of 344 stars includes only confirmed members of n…
Accretion Kinematics in the T Tauri Binary TWA 3A: Evidence for Preferential Accretion onto the TWA 3A Primary
Johns-Krull, Christopher M.; Tofflemire, Benjamin M.; Mathieu, Robert D.
We present time-series, high-resolution optical spectroscopy of the eccentric T Tauri binary TWA 3A. Our analysis focuses on variability in the strength and structure of the accretion-tracing emission lines Hα and He I 5876 Å. We find emission line strengths to display the same orbital phase-dependent behavior found with time-series photometry, na…
From Scattered-light to Millimeter Emission: A Comprehensive View of the Gigayear-old System of HD 202628 and its Eccentric Debris Ring
Hughes, A. Meredith; Wilner, David J.; Stapelfeldt, Karl R. +13 more
We present here new observations of the eccentric debris ring surrounding the Gyr-old solar-type star HD 202628: at millimeter wavelengths with ALMA, at far-infrared wavelengths with Herschel, and in scattered light with the Hubble Space Telescope (HST). The ring inner edge is found to be consistent between ALMA and HST data. As radiation pressure…
Characterizing K2 Candidate Planetary Systems Orbiting Low-mass Stars. IV. Updated Properties for 86 Cool Dwarfs Observed during Campaigns 1-17
Vanderburg, Andrew; Schlieder, Joshua E.; Crepp, Justin R. +15 more
We present revised stellar properties for 172 K2 target stars that were identified as possible hosts of transiting planets during Campaigns 1-17. Using medium-resolution near-infrared spectra acquired with the NASA Infrared Telescope Facility/SpeX and Palomar/TripleSpec, we found that 86 of our targets were bona fide cool dwarfs, 74 were hotter dw…
Spitzer Microlensing Parallax for OGLE-2017-BLG-0896 Reveals a Counter-rotating Low-mass Brown Dwarf
Helling, Christiane; Maoz, Dan; Tan, Thiam-Guan +69 more
The kinematics of isolated brown dwarfs in the Galaxy, beyond the solar neighborhood, is virtually unknown. Microlensing has the potential to probe this hidden population, as it can measure both the mass and five of the six phase-space coordinates (all except the radial velocity) even of a dark isolated lens. However, the measurements of both the …
The Mass-Activity Relationships in M and K Dwarfs. I. Stellar Parameters of Our Sample of M and K Dwarfs
Doyle, J. G.; Mullan, D. J.; Butler, C. J. +3 more
Empirical correlations between stellar parameters such as rotation or radius and magnetic activity diagnostics require estimates of the effective temperatures and the stellar radii. The aim of this study is to propose simple methods that can be applied to large samples of stars in order to derive estimates of the stellar parameters. Good empirical…
New Substellar Discoveries from Kepler and K2: Is There a Brown Dwarf Desert?
Latham, David W.; Carmichael, Theron W.; Vanderburg, Andrew M.
We present the discoveries of a brown dwarf (BD) and a low-mass star from the Kepler and K2 missions. The newly discovered BD is EPIC 212036875b and the low-mass star is KOI-607b. EPIC 212036875b has a mass of M b = 52.3 ± 1.9 M J, a radius of R b = 0.874 ± 0.017 R J, and orbits its host star in P = …