The double associated production of charmed particles by the interaction of 350 GeV/cπ− mesons with emulsion nuclei

Evidence is reported for the simultaneous production of four charmed particles in interactions induced by 350 GeV/c π− mesons in stacks of nuclear emulsions. The events were found during a search for beauty particles among a sample of about 200 interactions with candidates for charmed particles. The events selected required the presence of at least one muon with a high component of momentum transverse to the beam direction.