Radio Observations of Carbon Monoxide Towards Zeta Ophiuchi: Velocity Structure, Isotopic Abundances, and Physical Properties.

We present a map of the sup 12 CO (1-0) emission from the region around Zeta Oph at high spectral resolution and high signal to noise, and report a detection of sup 13 CO along the line of sight to the star. The CO emission towards the star arises from at least four components with peak emission at -2.0, - 0.7, 0.00, and +0.6 km s sup (-1), each with intrinsic velocity dispersion ~ 0.2 km s sup (-1). About one half of the total CO column density of 2x10 sup 15 cm sup (-2) is in the main component at -0.7 km s sup (-1), and the emission from all of the components appears to be optically thin.