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Purple dwarfs : New L subdwarfs from UKIDSS and SDSS
(EDP Sciences, 2013)
The first L subdwarf was a discovered only ten years ago. Less than ten L subdwarfs been published in the literature to date. Metal-poor ultracool atmospheres has not been well understood. Halo mass function cross substellar ...
The Properties of the 500 K Dwarf UGPS J072227.51-054031.2, and a Study of the Far-Red Flux of Cold Brown Dwarfs
(2012-04-01)
We present i and z photometry for 25 T dwarfs and one L dwarf. Combined with published photometry, the data show that the i - z, z - Y and z - J colors of T dwarfs are very red, and continue to increase through to the ...
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 ...
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. ...
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 ...
Discovery of the first white dwarf + T dwarf binary system and the use of white dwarfs as age calibrators
(American Institute of Physics (AIP), 2010)
We present the discovery of the first white dwarf + T dwarf binary system. Systems containing a white dwarf and a brown dwarf are rare but can be used to place constraints on the age of the binary, making them valuable ...
47 new T dwarfs from the UKIDDS large area survey
(2010)
We report the discovery of 47 new T dwarfs in the Fourth Data Release (DR4) from the Large Area Survey (LAS) of the United Kingdom Infrared Telescope (UKIRT) Infrared Deep Sky Survey with spectral types ranging from T0 to ...