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We report some results on charm photoproduction at γ energies ranging from 20 to 70 GeV. 36 events with pairs of charmed particles have been found in emulsions. The computed total cross section is (230±57)nb/nucleon. Frequencies of different production channels and some distributions are presented and compared with the predictions from a photon-gluon fusion model with string fragmentation

A precision measurement of the A 0 lifetime has been made in a helium bubble chamber. An exposure to a stopping K~ beam yielded 2239 A°'s, with a mean momentum of ~250 MeV/c, which satisfied rigorous selection criteria designed to minimize biases. The mean lifetime was found to be r = (2.36±0.06)X10~1 0 sec.