he transport of neutrons in a multiplying system is an area of branching processes which has extremely useful applications in the diagnostics of nuclear systems, yet this theory has never been summarised and described in such an in-depth manner before.

The lack of such a treatise has become apparent, especially since new fields and the appearance of new reactor concepts are being realised constantly.

This book has been written with two objectives in mind. The first part presents an account of the mathematical tools used in describing branching processes, which are then used to derive a large number of properties of the neutron distribution in multiplying systems with or without an external source.

The second part studies the theory applied to the description of the neutron fluctuations in nuclear reactor cores as well as in small samples of fissile material. The method of how to extract information regarding the system under scrutiny is discussed. In particular the measurement of the reactivity of sub-critical cores, driven with various Poisson and non-Poisson (pulsed) sources and the identification of fissile material samples is illustrated.

This book will be an invaluable source of information for graduate students as well as researchers in the fields of nuclear engineering, reactor physics, safeguards, as well as physicists and biologists working with branching processes.