Albedo particle rejection with the RICH study prototype of AMS

An experimental test has been performed on the Ring Imaging Cherenkov (RICH) study prototype of AMS, with cosmic ray particles on the ground, to evaluate the counter performance for Albedo particle rejection. The test was made with two radiators : Sodium Fluoride crystal (NaF, n≈1.33) and Silica Aerogel (n=1.035). The experimental results are shown and can be consistently accounted for on the basis of random events generated from PMT background counting by means of a simple model, used to estimate the Albedo rejection performance of the future AMS RICH.