Neutron Fluctuations

CHAPTER SIX

BRANCHING PROCESSES IN A RANDOMLY VARYING MEDIUM

Contents

6.1 Characterisation of the Medium

6.2 Description of the Process

6.3 Factorial Moments, Variances

6.4 Random Injection of the Particles

So far, it has been assumed that the parameters Q,f_k, k = 0, 1, 2, … determining the state of the multiplying system are constant. In many cases, however, these parameters are random processes or random variables themselves. Several studies in the mathematical literature [29–32] deal with discrete or continuous time branching processes taking place in a randomly varying medium. These investigations are aimed mostly to the study the probability of extinction or the asymptotical characteristics of the supercritical state. Our ambition here ...