Muon system of SND detector

Abstract

The Spherical Neutral Detector muon system composed of proportional tubes and plastic scintillation counters is described. This system is constructed for the SND detector collecting data at VEPP-2000 e + e − collider. The results of the muons and pions detection efficiency measurements are presented. These measurements are performed using e + e − → µ + µ − , e + e − → π + π − , e + e − → π + π − π 0 π 0 , e + e − → e + e − processes and cosmic muons. Efficiency for muons is 95.5% for the energies 0.6-1.0 GeV and becomes much lower in energy range 0.45-0.60 GeV. Pions detection efficiency varies from 0 at 0.4 GeV to 56% at 1.0 GeV. Probability of the muon system hit from electon/positron is no more than 0.43%. KEYWORDS: Particle identification methods; Wire chambers(MWPC, Thin-gap chambers, drift chambers, drift tubes, proportional chambers etc); Gaseous detectors; Scintillators, scintillation and light emission processes (solid, gas and liquid scintillators)