CN, CH, and CH(+) toward Zeta Ophiuchi

Observations with a resolution of 600,000 of interstellar absorption from the CN 3874.6 A, CH 4300.3 A, and CH(+) 4232.5 A lines reveal several new features of the clouds along the line of sight toward Zeta Oph. The CN line consists of two overlapping components which are similar to those seen in the CO pure rotational lines. The CH(+) line is well described by a single Gaussian line profile with FWHM of 3.5 km/s. The CH profile is a composite of a CN-like profile and a CH(+)-like profile, indicating for the first time that CH exists in two regions of very different character.