THE PRODUCTION OF HIGH-ENERGY KNOCK-ON ELECTRONS AND BREMSSTRAHLUNG BY μ-MESONS

Abstract

A multiplate cloud chamber experiment has been carried out to study the electromagnetic interactions of μ-mesons in iron and lead target materials. Energetic interactions which occurred inside the chamber were selected by an arrangement of plastic scintillators and Geiger counters; the total track lengths, and hence the energies, of the associated electron showers were measured by a photometric method combined with scintillator measurements. When Bremsstrahlung is the dominant process, the measured production probabilities are in good agreement for energy transfers in the range from about 8 to 40 Bev. When the production of knock-on electrons is the dominant process, good agreement with theory is obtained for energy transfers around 4.5 Bev but only fair agreement is obtained for higher energy transfers.