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A method for selecting M dwarfs with an increased likelihood of unresolved ultracool companionship
(2016-04-01)
Locating ultracool companions to M dwarfs is important for constraining low-mass formation models, the measurement of substellar dynamical masses and radii, and for testing ultracool evolutionary models. We present an ...
A large spectroscopic sample of L and T dwarfs from UKIDSS LAS : peculiar objects, binaries, and space density
(2015-06-01)
We present the spectroscopic analysis of a large sample of late-M, L, and T dwarfs from UKIDSS. Using the YJHK photometry from ULAS and the red-optical photometry from SDSS we selected a sample of 262 brown dwarf candidates ...
Discovery of a new Y dwarf: WISE J030449.03-270508.3
(2014-10-21)
We present a new Y dwarf, WISE J030449.03−270508.3, confirmed from a candidate sample designed to pick out low-temperature objects from the Wide-field Infrared Survey Explorer (WISE) data base. The new object is typed Y0pec ...
The extremely red L dwarf ULAS J222711-004547-dominated by dust
(2014-03)
We report the discovery of a peculiar L dwarf from the United Kingdom Infrared Deep Sky Survey Large Area Survey, ULAS J222711-004547. The very red infrared photometry (MKO J-K = 2.79 +/- 0.06, WISEW1-W2 = 0.65 +/- 0.05) ...
Parallaxes of Five L Dwarfs with a Robotic Telescope
(2014-01-01)
We report the parallax and proper motion of five L dwarfs obtained with observations from the robotic Liverpool Telescope. Our derived proper motions are consistent with published values and have considerably smaller errors. ...
A spectroscopic and proper motion search of Sloan Digital Sky Survey : red subdwarfs in binary systems
(2013-09)
Red subdwarfs in binary systems are crucial for both model calibration and spectral classification. We search for red subdwarfs in binary systems from a sample of high proper motion objects with Sloan Digital Sky Survey ...
NPARSEC : NTT Parallaxes of Southern Extremely Cool objects. Goals, targets, procedures and first results
(2013-08)
The discovery and subsequent detailed study of T dwarfs have provided many surprises and pushed the physics and modelling of cool atmospheres in unpredicted directions. Distance is a critical parameter for studies of these ...
76 T dwarfs from the UKIDSS LAS : benchmarks, kinematics and an updated space density
(2013-07)
We report the discovery of 76 new T dwarfs from the UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). Near-infrared broad- and narrow-band photometry and spectroscopy are presented for the new objects, along ...
Two new ultracool benchmark systems from WISE+2MASS
(2013-05)
We have used the Two-Micron All-Sky Survey and the Wide-field Infrared Survey Explorer to look for ultracool dwarfs that are part of multiple systems containing main-sequence stars. We cross-matched L dwarf candidates from ...
The sub-stellar birth rate from UKIDSS
(2013-04)
We present a new sample of mid-L to mid-T dwarfs with effective temperatures of 11001700 K selected from the UKIDSS Large Area Survey (LAS) and confirmed with infrared spectra from X-shooter/Very Large Telescope. This ...