Probing the OH in Hale-Bopp

B.J. Butler (NRAO), P. Palmer (UChicago)

We observed the occultation of 3 compact radio sources by the OH in the coma of comet Hale-Bopp. Both the 1667 and 1665 MHz lines of OH were observed. The 1667 MHz spectra are shown below. In at least one of the experiments, the signal was strong enough to produce a profile of OH column density and 1667/1665 ratio as a function of position along the path of the background source relative to the comet nucleus. The detailed results from these occultation events will be discussed, along with implications.