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We have used the integral field spectrograph OSIRIS and laser guide staradaptive optics at Keck Observatory to obtain high angular resolution (0.06"),moderate spectral resolution (R ~ 3800) images of the bipolar jet from theHerbig Ae star LkHa 233, seen in near-IR [Fe II] emission at 1.600 & 1.644microns. This jet is narrow and tightly collimated, with an opening angle ofonly 9 degrees, and has an average radial velocity of ~ 100 km/s. The jet andcounterjet are asymmetric, with the red-shifted jet much clumpier than itscounterpart at the angular resolution of our observations. The observedproperties are in general similar to jets seen around T Tauri stars, though ithas a relatively large mass flux of (1.2e-7 +- 0.3e-7) M_sun/year, near thehigh end of the observed mass flux range around T Tauri stars. We alsospatially resolve an inclined circumstellar disk around LkHa 233, whichobscures the star from direct view. By comparison with numerical radiativetransfer disk models, we estimate the disk midplane to be inclined i = 65 +- 5degrees relative to the plane of the sky. Since the star is seen only inscattered light at near-infrared wavelengths, we detect only a small fractionof its intrinsic flux. Because previous estimates of its stellar properties didnot account for this, either LkHa 233 must be located closer than thepreviously believed, or its true luminosity must be greater than previouslysupposed, consistent with its being a ~4 M_sun star near the stellar birthline.

Laser Guide Star Adaptive Optics Integral Field Spectroscopy of a Tightly Collimated Bipolar Jet from the Herbig Ae star LkHa 233