Interstellar K I and Na I absorption lines near RHO Ophiuchi

Interferometric scans of the interstellar K I lambda7699 and Na I D1 absorption lines have been obtained toward rho Oph and o Sco, in the rho Ophiuchi dark cloud. The scans reveal narrow, multiple lines toward rho Oph. This multiplicity can explain the difference in radial velocity between the strong atomic absorption lines and the weak molecular lines in this direction, as observed at lower velocity resolution. In both directions the less saturated lambda7699 lines yield K I column densities roughly consistent with the reddening