Population dynamics in Nuclear Engineering Theory and applications

by Chen Dubi

at Physics Colloquium

Tue, 15 Nov 2016, 15:00
Nanotechnology institute building (#51) room 15

Abstract

In recent years there is a growing interest in population dynamics and pattern formation showing application in wide range of eras of such as Biology Chemistry Sociology Ecology and more It is less known that population dynamics are also frequently used in nuclear science and engineering since the distribution of the number of neutrons in a fission chain can be described as a continuous time Markovian branching process where the fission is described as a branching event and the absorption leakage of a neutron is described as a death event From a physical point of view population dynamics in nuclear science have two very distinct attributes with respect to other fields : First since the fuel burnup and the neutron lifetime have different timescales we can assume endless resources Second the population size is huge varying from 109 in very small zero power reactors to 1019 if full scale power reactors There for many of the typical questions studied biological models such as the mean time to extinction of a meta stable population are simply not relevant On the other hand for the exact same reasons the short average lifetime and the large size of the population sampling the statistical properties of the neutron population and implementing the theory in reactor measurements is a common practice often referred to as Reactor Noise Experiments In the talk we will discuss the theory and implementation of perhaps the most basic noise experiments: the so called Feynman experiment and introduce two recent contributions: analytic formulas for the expected statistical error in the Feynman experiments and a new modelling approach to reactor noise via stochastic differential equations The results will be demonstrated through a set of experiments conducted on the MINERVE research rector Refreshments are served at 14:45

Created on 14-11-2016 by Bar Lev, Yevgeny (ybarlev)
Updaded on 14-11-2016 by Bar Lev, Yevgeny (ybarlev)