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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 ...
Discovery of a brown dwarf companion to the A3V star β Circini
(2015-12-21)
We report the discovery of an L dwarf companion to the A3V star β Circini. VVV J151721.49−585131.5, or β Cir B, was identified in a proper motion and parallax catalogue of the VISTA Variables in the Vía Láctea survey as ...
The EChO science case
(2015-12-01)
The discovery of almost 2000 exoplanets has revealed an unexpectedly diverse planet population. Observations to date have shown that our Solar System is certainly not representative of the general population of planets in ...
Probing M subdwarf metallicity with an esdK5+esdM5.5 binary
(2015-10-15)
We present a spectral analysis of the binary G 224-58 AB that consists of the coolest M extreme subdwarf (esdM5.5) and a brighter primary (esdK5). This binary may serve as a benchmark for metallicity measurement calibrations ...
Starspot distributions on fully convective M dwarfs : implications for radial velocity planet searches
(2015-10-07)
Since M4.5 - M9 dwarfs exhibit equatorial rotation velocities of order 10 km/s on average, radial velocity surveys targeting this stellar population will likely need to find methods to effectively remove starspot jitter. ...
ABSOLUTE PROPER MOTIONS OUTSIDE the PLANE (APOP) - A STEP TOWARD the GSC2.4
(2015-10-06)
We present a new catalog of absolute proper motions and updated positions derived from the same Space Telescope Science Institute digitized Schmidt survey plates utilized for the construction of Guide Star Catalog II. As ...
49 new T dwarfs identified using methane imaging
(2015-07-01)
We present the discovery of 49 new photometrically classified T dwarfs from the combination of large infrared and optical surveys combined with follow-up TNG photometry. We used multi-band infrared and optical photometry ...
Benchmarking the power of amateur observatories for TTV exoplanets detection
(2015-07-01)
We perform an analysis of ~80000 photometric measurements for the following 10 stars hosting transiting planets: WASP-2, -4, -5, -52, Kelt-1, CoRoT-2, XO-2, TrES-1, HD 189733, GJ 436. Our analysis includes mainly transit ...
Methane and ammonia in the near-infrared spectra of late-T dwarfs
(2015-06-11)
Analysis of T dwarfs using model atmospheres has been hampered by the absence of reliable line lists for methane and ammonia. Newly computed high-temperature line lists for both of these important molecules are now available, ...
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 ...