Related papers: Four nearby L dwarfs

We present a 0.6-4.1 micron spectroscopic sequence of M, L, and T dwarfs. The spectra have R~2000 from 0.9 to 2.4 microns and R=2500-200 from 2.9 to 4.1 microns. These new data nearly double the number of L and T dwarfs that have reported…

We present 6300--10100 {\AA} spectra for a sample of 13 T dwarfs observed using LRIS mounted on the Keck I 10m Telescope. A variety of features are identified and analyzed, including pressure-broadened K I and Na I doublets; narrow Cs I and…

We present near-infrared spectra for a sample of T dwarfs, including eleven new discoveries made using the Two Micron All Sky Survey. These objects are distinguished from warmer (L-type) brown dwarfs by the presence of methane absorption…

We present the discovery of two nearby L dwarfs from our 2MASS proper motion search, which uses multi-epoch 2MASS observations covering ~4700 square degrees of sky. 2MASS J18212815+1414010 and 2MASS J21481628+4003593 were overlooked by…

In this contribution, I discuss some of the salient features of L and T dwarf spectra in both the red optical (6300--10000 {\AA}) and near-infrared (1--2.5 $\micron$) wavelength regimes. Important absorption bands and lines, including those…

We have obtained near-infrared spectra of three L dwarfs discovered by 2MASS, 1506+13 (L3), 1507-16 (L5), and 0920+35 (L6.5). From the comparison of the H and K band spectra of these L dwarfs, we have found the presence of methane…

We report the identification of 2MASS J15500845+1455180 as a 0"9 L dwarf visual binary. This source is resolved in Sloan Digital Sky Survey (SDSS) images and in near-infrared imaging with the IRTF SpeX imager/spectrometer. The two…

We identify the L dwarf 2MASS J20261584-2943124 as an unresolved spectral binary, based on low-resolution, near-infrared spectroscopy from IRTF/SpeX. The data reveal a peculiar absorption feature at 1.6 microns, previously noted in the…

We present the peculiar near-infrared spectrum of the newly discovered brown dwarf 2MASS J05185995-2828372, identified in the Two Micron All-Sky Survey. Features characteristic of both L and T dwarfs are present, namely strong carbon…

L dwarfs exhibit low-level, rotationally-modulated photometric variability generally associated with heterogeneous, cloud-covered atmospheres. The spectral character of these variations yields insight into the particle sizes and vertical…

We present optical (6500-9200A) spectroscopy of eight cool dwarfs detected in a 231 square degree ``Mini-survey'' of the Deep NEar Infrared Survey (DENIS) data. We are able to confirm that the spectral types derived from the Mini-survey…

We present infrared spectra of brown dwarfs with spectral types from mid-L to T. The 0.9-2.5 $\mu$m spectra of three dwarfs found by the Sloan Digital Sky Survey contain absorption bands of both methane and carbon monoxide and bridge the…

We present the first results of a near-infrared (0.96-2.31 micron) spectroscopic survey of M, L, and T dwarfs obtained with NIRSPEC on the Keck II telescope. Our new survey has a resolving power of R = 2000 and is comprised of two major…

We present a $L$-band (2.98--3.96$\mu$m) spectroscopic study of 8 young L dwarfs with spectral types ranging from L2 to L7. Our spectra (${\lambda}/{\Delta \lambda}\approx$ 250 to 600) were collected using the Gemini Near-InfraRed…

We present the discovery of seven new T dwarfs identified in the Two Micron All Sky Survey. Low-resolution (R$\sim$150) 0.8--2.5 micron spectroscopy obtained with the IRTF SpeX instrument reveal the characteristic H$_2$O and CH$_4$ bands in…

We present medium-resolution z-, J-, and H-band spectra of four late-type dwarfs with spectral types ranging from M8 to L7.5. In an attempt to determine the origin of numerous weak absorption features throughout their near-infrared spectra,…

We present a sequence of high resolution (R~20,000 or 15 km/s) infrared spectra of stars and brown dwarfs spanning spectral types M2.5 to T6. Observations of 16 objects were obtained using eight echelle orders to cover part of the J-band…

We present a low-resolution (R = 90), 5.5-38 micron spectral sequence of a sample of M, L, and T dwarfs obtained with the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope. The spectra exhibit prominent absorption bands of…

Evidence is presented that 2MASS J03202839-0446358, a late-type dwarf with discrepant optical (M8:) and near-infrared (L1) spectral types, is an as-yet unresolved stellar/brown dwarf binary with late-type M dwarf and T dwarf components.…

We present the first parallax and luminosity measurements for an L subdwarf, the sdL7 2MASS J05325346+8246465. Observations conducted over three years by the USNO infrared astrometry program yield an astrometric distance of 26.7+/-1.2 pc…