1ST RESULTS FROM THE UHRF - ULTRA-HIGH-RESOLUTION OBSERVATIONS OF INTERSTELLAR CH, CH-OPHIUCHI( AND CN TOWARDS ZETA)

We present ultra-high-resolution observations (R > 700000) of interste llar CH, CH+ and CN towards zeta Oph obtained with the newly commissio ned Ultra-High-Resolution Facility (UHRF) at the AAT. The molecular li nes have all been fully resolved, and we discuss their implications fo r this well-studied molecular sightline. The CH and CN lines each cons ist of two narrow (b almost-equal-to 0.5 km s-1) components separated by 1.13 +/- 0.10 km s-1; an additional broad (b = 1.8 km s-1) componen t is present in CH. We show that the very broad (b = 2.1 km s-1) CH+ l ine profile is consistent with the formation of this molecule in warm haloes surrounding the cold cores responsible for the narrow CH and CN components.