The momentum spectrum of mouns in large extensive air showers

Abstract

This thesis describes the construction and operation of a magnet spectrograph designed to measure the momentum spectrum of muons in Extensive Air Showers (EAS) detected by the three air shower arrays at Haverah Park near Harrogate.The introduction contains a summary of the properties of air-showers and the various models of high energy interactions andcascade theories proposed to explain the observed phenomena, A survey of previous measurements on the momentum spectrum of muons in EAS is followed by an outline description of the present experiment and its aims. The design and preliminary measurements carried out on the spectrograph are detailed in Chapter 2, together with the evaluation of the maximum detectable momentum, and the derivation of the acceptance function of the instrument. The extensive air shower arrays, which detect showers with sizes from 10(^5) to 10(^8) particles, are described in chapter 3, followed by a simplified form of air shower analysis, used for the smaller arrays. Previous experiments using solid-iron magnets have relieved on relaxation method to derive the incident momentum spectrum, which is suitable only when a good approximation to the spectrum is known beforehand. A second method of analysis is presented in Chapter 4, and the results are compared with the relaxation method. Good agreement is found. Chapter 5 contains the preliminary results of the experiment, and a comparison with previous results and the predictions of theoretical models. Finally, an assessment is made of the future work judged to be most useful for comparison with the theoretical models.