Recognition of Cherenkov patterns in high multiplicity environments

An algorithm for the recognition of Cherenkov patterns based on the Hough Transform Method (HTM), modified for signals with intrinsic width in presence of background, is presented. The method basically consists in a mapping of the pad coordinate space directly to the Cherenkov angle parameter space with a crucial increase of performance in the treatment of different pattern shapes and amount of background. The method has been developed in the framework of the ALICE experiment at CERN for the analysis of data taken in the HMPID (High Momentum Particle IDentification) RICH detector prototype test beam.