Theoretical Studies of the Longitudinal Development of Extensive Air Showers. II: Average Behaviour of the Electron Component

Abstract

The longitudinal development of the electron component of the air shower is investigated in connection with high energy nuclear interaction. The method of calculations and analyses developed for the study of the nuclear active component in a previous paper are used again. The transition curves of the electrons are considered. First, the transition curves are represented by four numerical constants. Next, model dependent features of the transition curves are discussed by investigating systematically the relationship between the four constants and parameters in the model of high energy nuclear interaction. From the results of the present work, a model of the longitudinal development of the electron component is presented, and is compared with other models ancl other simulations of air showers. § ] . lntrod ueLion The purpose of the present work is to provide a systematic view of the relationship between the basic properties of high energy nuclear interaction and the characteristic features of the longitudinal development of the air shower. In this paper, following the investigation of the nuclear active component of the air shower grven m a previous paper (hereafter referred to as PJ), we deal with the electron ,·ornponent in a similar way. The transition curves of the electnms, under consideration in the present paper, would be of great use in understanding the experimental data such as the size spectra at various altitudes, the angular distribution of the air showers 21 and the direct measurement of the transition curves by air scintillation light. 31 In the present and the previous paper, however, our investigations are restricted to the average transition curves of the fixed primary energy. For precise comparison of the theoretical results with experimental data, the fluctuations of the transition curves haYe to be taken into account. Stochastic properties of the transition curves due to fluctuations in the nuclear collisions vvill be discussed in detail in a following paper. In the coun>e of the present work, \Ve have found that the transition curves