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Effective temperatures, rotational velocities, microturbulent velocities and abundances in the atmospheres of the Sun, HD1835 and HD10700
(2012)
We describe our procedure to determine effective temperatures, rotational velocities, microturbulent velocities, and chemical abundances in the atmospheres of Sun-like stars. We use independent determinations of iron ...
Discovery of the benchmark metal poor T8 dwarf BD+01 2920B
(2012)
We have searched the Wide-field Infrared Survey Explorer first data release for widely separated (<=10,000AU) late T dwarf companions to Hipparcos and Gliese stars. We have discovered a new binary system containing a K-band ...
Application of Bayesian model inadequacy criterion for multiple data sets to radial velocity models of exoplanet systems
(2011-08)
We present a simple mathematical criterion for determining whether a given statistical model does not describe several independent sets of measurements, or data modes, adequately. We derive this criterion for two data sets ...
The properties of the T8.5p dwarf Ross 458C
(2011-07)
We present near-infrared photometry and spectroscopy, and warm-Spitzer IRAC photometry of the young very cool T dwarf Ross 458C, which we have typed as T8.5p. By applying the fiducial age constraints (<= 1 Gyr) imposed by ...
Blue not brown: UKIRT Infrared Deep Sky Survey T dwarfs with suppressed K-band flux
(2011-06)
We have used blue near-infrared colours to select a group of 12 spectroscopically confirmed United Kingdom InfraRed Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) T dwarfs later than T4. From amongst these, we identify ...
The discovery of the T8.5 dwarf UGPS J0521+3640
(2011-06)
We have carried out a search for late-type T dwarfs in the UKIRT Infrared Deep Sky Survey Galactic Plane Survey 6th Data Release. The search yielded two persuasive candidates, both of which have been confirmed as T dwarfs. ...
Parallaxes of southern extremely cool objects. I. : Targets, proper motions, and first results
(2011)
We present results from the PARallaxes of Southern Extremely Cool objects ( PARSEC) program, an observational program begun in 2007 April to determine parallaxes for 122 L and 28 T southern hemisphere dwarfs using the Wide ...
Chromospheric activities and kinematics for solar type dwarfs and subgiants : analysis of the activity distribution and the AVR
(2011)
Aims : In this work we present chromospheric activity indices, kinematics, radial-velocities, and rotational velocities for more than 850 FGK-type dwarfs and subgiant stars in the southern hemisphere and test how best to ...
Low-mass Objects in Moving Groups
(Astronomical Society of the Pacific, 2010)
We present here the kinematic study of part of a 132 target sample of low-mass objects, previously selected by photometric and astrometric criteria as possible members to five young moving groups (MGs): Local Association ...
A search for southern ultracool dwarfs in young moving groups
(2010)
We associate 132 low-mass ultracool dwarfs in the southern hemisphere as candidate members of five moving groups (MGs) using photometric and astrometric selection techniques. Of these objects, we present high-resolution ...