13 papers
Infrared Colors of L and T Dwarfs
S. K. Leggett, D. A. Golimowski, X. Fan +2
We discuss the behaviour of the JHKL'M' colors of L and T dwarfs, based on photometric and spectroscopic data obtained at the United Kingdom Infrared Telescope in Hawaii. We have m…
Infrared Classification of L and T Dwarfs
T. R. Geballe, G. R. Knapp, S. K. Leggett +2
We use new and published medium resolution 0.6--2.5 m spectra of L and T dwarfs to develop a unified classification system for both of these new spectral classes. Two indices of…
Detection of H3+ in the interstellar medium of IRAS 08572+3915
T. R. Geballe
The first detection of the molecular ion H3+ in an extragalactic object has been made toward the highly obscured ultraluminous galaxy, IRAS 08572+3915. Two absorption features near…
Extreme BAL Quasars from the Sloan Digital Sky Survey
Patrick B. Hall, J. E. Gunn, G. R. Knapp +16
The Sloan Digital Sky Survey has discovered a population of broad absorption line quasars with various extreme properties. Many show absorption from metastable states of FeII with…
Multiwavelength observations revealing the outbursts of the two soft X-ray transients XTE J1859+226 and XTE J1118+480
S. Chaty, C. A. Haswell, R. I. Hynes +9
We report here on multiwavelength observations of the two new soft X-ray transients (SXTs) XTE J1859+226 and XTE J1118+480, which we observed with HST/RXTE/UKIRT. For XTE J1118+480…
Infrared Spectroscopy of Brown Dwarfs: the onset of methane absorption in L dwarfs and the L/T transition
T. R. Geballe, K. S. Noll, S. K. Leggett +3
We present infrared spectra of brown dwarfs with spectral types from mid-L to T. The 0.9-2.5 m spectra of three dwarfs found by the Sloan Digital Sky Survey contain absorption b…