AUTOMATED TRACK RECOGNITION AND EVENT RECONSTRUCTION IN NUCLEAR-EMULSION

The major advantages of nuclear emulsion for detecting charged particl es are its submicron position resolution and sensitivity to minimum io nizing particles. These must be balanced, however, against the difficu lt manual microscope measurement by skilled observers required for the analysis. We have developed an automated system to acquire and analyz e the microscope images from emulsion chambers. Each emulsion plate is analyzed independently, allowing coincidence techniques to be used in order to reject background and estimate error rates. The system has b een used to analyze a sample of high-multiplicity Pb-Pb interactions ( charged particle multiplicities similar to 1100) produced by the 158 G eV/c per nucleon Pb-208 beam at CERN. Automatically measured events ag ree with our best manual measurements on 97% of all the tracks. We des cribe the image analysis and track reconstruction techniques, and disc uss the measurement and reconstruction uncertainties.