Recognition of Cherenkov ring patterns with the HMPID-RICH detector in ALICE at LHC

Abstract A high momentum particle identification detector (HMPID) covering about 5% of the ALICE central barrel region has been designed and prototyped. The detector consists of seven RICH modules with a proximity focusing geometry, covering 12 m 2 . The very large density of hits on the detector (80÷90 part/m 2 in the extreme cases) makes the recognition of the Cherenkov photon patterns a complex and crucial task. A study of the pattern recognition strategy based on the Hough transformation in terms of particle identification efficiency and particle contamination will be presented.