MUON DECAY, A POSSIBILITY FOR PRECISE MEASUREMENTS OF MUON CHARGE RATIO IN THE LOW ENERGY RANGE ( < 1 GEV/C)

摘要

The atmospheric flux of muons and neutrinos originates from the decay of charged pions and kaons produced by cosmic rays in the atmosphere. Muons have a relatively large lifetime and they decay in electrons and neutrinos. The muon charge ratio represents the ratio of positive to negative atmospheric muons. The measurements are performed using a small compact device, WILLK Weakly Ionizing Lepton Lead Interactions), by detecting the lifetime of the muons in different materials. Avoiding the difficulties of measurements with magnetic spectrometers, this method gives precise results on muon charge ratio especially in the low energy where the influence of magnetic field is stronger. In the present configuration the detector is construct as a rotatable device which permits measurements on different inclinations and azimuthal directions. Measurements of the muon charge ratio performed in the East - West directions with the detector inclined at 45° shows a pronounced Eas-West effect for the muon momentum range 0.35-0.50 GeV/c.