Line spectra in interstellar clouds. III - Weak lines below 3400 A in zeta Persei

A composite spectrum consisting of the sum of 36 photographic echellograms of Per is presented in order to study lines of interstellar Na 1, Ti ii, Be ii, NH, CH, and OH. It is found that Na is depleted by a factor of 3 and Ti by a factor of 1400 in the cloud. An upper limit of 600 i A is found for the equivalent width of the strongest Be ii resonance line which implies Y(Be)IN(H) < 1.3 x 10-11 toward Per. The implications of this upper limit are discussed in light of two depletion mechanisms in interstellar clouds. The upper limit of 250 A for the strongest NH line implies N(NH)!N(H) < 3.9 >c 10-10. The measurements of the C-X CH lines allow some remarks to be made concerning the f-values which should be used for all interstellar CH lines which lie in the visible spectrum. The two strongest A-X OH lines are detected and yield N(OH) = 5.3 x 1013 toward Per. The previously reported inconsistency between near-UV and Copernicus determinations of the OH column density is examined, and an astronomically determined f-value is suggested for the Al 222.07 line which removes the previous discrepancy. It is argued on theoretical grounds that this oscillator strength is more consistent with that expected from this transition than that resulting from the recent calculation by Ray and Kelly. Subject headings: interstellar: matter - interstellar: molecules - stars: individual - transition probabilities