Charm photoproduction results from E-691

High statistics charm data from Fermilab photoproduction experiment E-691 is used to address questions of production mechanisms, exclusive semileptonic decays and the spectroscopy of L = 1 cantiq meson resonances. For D mesons there is a small but significant favoring of antiparticle production in the xF > .2 region of acceptance of this experiment. To study production mechanisms, PT2 and xF distributions, and the energy dependence of the charm cross section are given. The exclusive semileptonic branching ratio D+ → antiK*0e+ν is observed to be 4.13 ± .38 ± .72% corresponding to a transition rate which is about .5 that of D → Keν decays. Significant longitudinal polarization is observed for the K* in the final state. The non-resonant contribution to D+ → K-π+e+ν is found to be only about 10% that of the K* component. Charmed meson resonances are observed at a mass of about 2420 MeV/c2 in the D*+π- final state and at a mass of approximately 2461 MeV/c2 in D+π-