Methods of Cherenkov pattern recognition in high multiplicity environments.

D. Di Bari 
for the ALICE Collaboration

    The High Momentum Particle Identification Detector (HMPID) in the ALICE experiment is based on a RICH detector with CsI photocathode. In such experiment, where the anticipated multiplicity will be high (~10,13% of pad occupancy in central PbPb events), the identification of charged particles requires an implementation of efficient pattern recognition algorithms.
    Results on the application of an algorithm based on the Hough transform, consisting of a mapping of the pad coordinate space directly to the Cherenkov angle parameter space, will be shown. Example on the performance of the method on real events in STAR, where a prototype of the RICH detector developed in the ALICE framework has been successfully operated, will be also shown.
    Moreover, the discrimination of Cherenkov signals coming from p, K and p using a novel technique of recent development ("Support Vector Machines") is under investigation.