The pomeron and the multiperipheral model

Abstract

In general this thesis is concerned with high energy elementary particle physics and in particular it discusses the interactions in the framework of the multiperipheral context. The first chapter is a general introduction to the field where different observables of interest, such as cross-section and multiplicity, are defined and discussed. In the second chapter after introducing different multi-particle production mechanisms, such as multiperipheral and diffractive models, we put more emphasis on the former and study different models of the type. The impact parameter space is a suitable place to work in, so we transform the multi-particle amplitude to this space and extract interesting results out of it in chapter 3. Especially the works of Henyey and Jedach-Turnau are emphasized in this chapter. We show that it is hard to reconcile the model with the experimentally observed radius of elastic scattering as a function of energy. The fourth chapter is about the interference diagrams of the multiperipheral model in the unitarity equation. As energy increases the number of such terms increases rapidly. We have estimated their effect in Henyey and Jedach-Tumau types of calculation and have added them to the 'standard' result. It is found that, as far as the radius is concerned, these extra terms (nl-l of them) do not make a significant contribution. In chapter five a modification of the basic multiperipheral amplitude is introduced in order to improve agreement with experiment. This successfully reproduces the known results.