The estimation of scanning efficiencies for experiments using visual detectors

Abstract

A new technique is presented for estimating scanning efficiencies. The special feature of this technique is that it allows for the tendency of different scanners to miss the same events. Each event is assumed to have a visibility, ν, depending both on its own characteristics and on the perceptiveness of the scanners. The distribution of events in visibility is described by a function F( ν) whose parameters are determined by comparing the numbers of new events found in each of three or more successive scans. The technique is applied to a study of μ + decay events, which have been scanned four times. The “true” number of events, N T = ʃ 0 1F(ν) dν , found by this technique and a lower limit to N T found by an alternate technique indicate that the inefficiency estimated by the usual double-scanning method can be low by a large factor.