Investigation of the cosmic-ray east–west asymmetry

Abstract

The east–west asymmetry has been measured to obtain a more accurate value of the antiproton–proton flux ratio in the primary cosmic radiation. The measurements have been carried out at middle latitudes at a depth of 10 g/cm2 of atmosphere and at a zenith angle of 60°. The telescope used for detection consisted of two scintillation counters, a lucite Cerenkov counter, and a gas Cerenkov counter. The threshold of the gas Cerenkov detector has been changed from 1.7 BeV to 5.2 BeV (for protons) in flight. For orientation of the device in space the earth's magnetic field was used.The preliminary results of the experiment are given.