THE FIRST HUNDRED BROWN DWARFS DISCOVERED BY THE WIDE-FIELD INFRARED SURVEY EXPLORER (WISE)

摘要: We present ground-based spectroscopic verification of 6 Y dwarfs (see also Cushing et al.), 89 T dwarfs, 8 L and 1 M dwarf identified by the Wide-field Infrared Survey Explorer (WISE). Eighty these are cold brown with spectral types ≥T6, six which have been announced earlier Mainzer al. Burgasser color-color color-type diagrams showing locus M, L, T, in WISE color space. Near-infrared and, a few cases, optical spectra presented for discoveries. classifications as late early objects peculiar discussed. Using new discoveries, we able to extend classification scheme from T8 T9. After deriving an absolute 4.6 μm (W2) magnitude versus type relation, estimate spectrophotometric distances our use available astrometric measurements provide preliminary trigonometric parallaxes four L9 pec (red), T8, T9, Y0; all lie within 10 pc Sun. The Y0 dwarf, 1541–2250, is closest at 2.8^(+1.3)_(–0.6) pc; if this 2.8 value persists after continued monitoring, 1541–2250 will become seventh stellar system Another objects, between T6 >Y0, distance estimates placing them pc. these, 1506+7027, believed fall ~4.9 multi-epoch positions supplemented positional info primarily Spitzer/Infrared Array Camera allow us calculate proper motions tangential velocities roughly one-half This work represents first step complete full-sky, volume-limited census late-T dwarfs. results census, preliminary, lower limits space density discuss constraints on both functional form mass function low-mass limit star formation.