A study of extensive air showers at sea level

Abstract

The lateral distribution of muons of energy E(_u) >500 MeU in E.A.S. of median size 3.10(^5) particles at sea level and their correlation to the electron structure function (shower age parameter) has been investigated using a large flash tube chamber operated in conjunction with the Durham E.A.S. array. The lateral distribution seems to be not dependent on shower size, but for the more inclined and older showers it tends to be flatter. Old showers of a given size are found to contain a greater total number of muons than young showers of the same size. A measurement of the size spectrum has been performed in which the size and collecting area take into account the age parameter of a single shower. Except at very small and large shower sizes, the spectrum shows a close agreement with the spectrum obtained assuming all showers obey the Greisen average lateral structure function. A search for charged e/3 particles (quarksj close to the core of E.A.S. has been carried out using the flash tube chamber. In 511.2 hours running time, 2 low efficiency tracks have been observed but none fulfil all the criteria as a genuine quark candidate. A search for any preferred arrival direction of showers in galactic coordinates has been carried out, The results show an overall isotropic primary flux but in the galactic chart two anomalous regions (regions with an excess of events) are observed. Correlation of the regions with the known cosmic ray sources (supernova remnants, pulsars, quasars, X andy -ray sources) have been studied.