D meson branching ratios and hadronic cross section

Charm particle decay vertices have been detected in the high resolution hydrogen bubble chamber LEBC and the decay products analysed downstream using a preliminary configuration of the European Hybrid Spectrometer, which allowed γ detection but had very limited particle identification capabilities. Data were taken with incident 360 GeV/c π- (7.8 ev/μb) and 360 GeV/c p (7.3 ev/μb). The bubble chamber film has been subjected to 2 independent scans plus a physicist check scan. After measurement, the charm decays were selected (from a large background consisting mostly of strange particle decays). The final sample consists of 72 events containing 103 detected charm decays. The background from non charm decays is less than 4%