Molecular Hydrogen Outflows in the Central Arcseconds of the T Tauri System

Abstract

We present new, near-infrared, adaptive optics observations of the enigmatic pre-main-sequence object T Tauri, using broadband filter imagery, long-slit spectroscopy, and Fabry-Perot imaging spectra. The broadband filter images spatially resolve the three stellar components of T Tau in the H, Ks, and L' photometric bands. We clearly detect T Tau Sb in the J band, and place upper limits on the J brightness of the infrared companion, T Tau Sa. The K-band spectrum of the T Tau S binary also resolves both components, and confirms strong Brγ emission in both stars and photospheric features in Sb. We also report 2.058 μm helium recombination radiation associated with T Tau Sb. The Fabry-Perot channel map centered on the v = 1-0 S(1) line of molecular hydrogen shows a number of spatially extended structures, including a loop of emission north of the stars that is also visible in continuum frames taken at ±900 km s-1 from the line center. The continuum-subtracted H2 image displays bow shock structures associated with the southeast-northwest and east-west outflows. The east-west jet system also shows bright, oblique shocks lining the flow channel. The part of the long-slit spectrum that overlaps this channel wall displays H2 line ratios consistent with shock heating. This region also corresponds to the brightest knot of UV fluorescent emission reported by Saucedo and coworkers. The Fabry-Perot images unambiguously identify T Tau S binary as the source of the east-west outflow, although we cannot yet determine which of the two components produces the jet.