Tuning of the emission frequency of a gas-discharge XeCl laser

Abstract

Results of an investigation on muons of energy greater than or equal to 150 GeV associated with extensive air showers are presented. The total number of muons is found to vary with shower size according to the relation ( l ; 10 4 7 + 0 -0 5 n,(>150,N) = ( 2 7 i 7 )for lo5 < N < 5 x lo6. An increase in the power index c( = d In n,/d In N is indicated for N < 10'. Theenergyspectrumofthemuonsisfoundto beapowerlawofthetypeE;"30*0"6 for 150 GeV < E , < 640 GeV. The observed variation of n,, with N is found to be flatter than the one predicted by known EM models for constant primary composition. A primary composition varying with primary energy and/or an energy dependent change in characteristics of nuclear interaction at high energies is suggested to account for the observed results.