Cellular techniques for Ring Imaging Cherenkov detector image processing

Ring Imaging Cherenkov detectors (RICH) are a class of particle detectors used for particle identification whose principle involves a pattern recognition problem: identifying circles from a short number of their points. A real image hosts several circles which may eventually overlap. Actual techniques solving this problem are mainly non-local algorithms implemented on software requiring large computing time and resources. This point limits the use of RICH detectors in the trigger system of large experiments such as LHCb. An alternative solution, based on a cellular approach, is proposed. A list of possible templates from the standard library is established and considerations on the requirements for the hardware implementation in FPGAs are given. From the conceptual point of view, the cellular technique solution looks promising while the hardware implementation in FPGAs lays in the verge of the actual technical limitations if response times are to be in the order of the microsecond as required in the LHCb hardware trigger.