2007ApJ...670..499P

We have used the integral field spectrograph OSIRIS and laser guide star adaptive optics at Keck Observatory to obtain high angular resolution (0.06"), moderate spectral resolution (R≃3800) images of the bipolar jet from the Herbig Ae star LkHα 233, seen in near-IR [Fe II] emission at 1.600 and 1.644 µm. This jet is narrow and tightly collimated, with an opening angle of only 9°, and has an average radial velocity of ∼100 km/s. The jet and counterjet are asymmetric, with the redshifted jet much clumpier than its counterpart at the angular resolution of our observations. The observed properties are in general similar to jets seen around T Tauri stars, although it has a relatively large mass flux of 1.2±0.3x10^–7 M_☉/yr, near the high end of the observed mass flux range around T Tauri stars. We also spatially resolve an inclined circumstellar disk around LkHα 233, which obscures the star from direct view. By comparison with numerical radiative transfer disk models, we estimate the disk midplane to be inclined i=65°±5° relative to the plane of the sky. Since the star is seen only in scattered light at near-infrared wavelengths, we detect only a small fraction of its intrinsic flux. Because previous estimates of its stellar properties did not account for this, either LkHa 233 must be located closer than previously believed, or its true luminosity must be greater than previously supposed, consistent with its being a ∼4 M_☉ star near the stellar birth line.