Neutral particles are fired at normal incidence into a purely absorbing slab of…
PHYSICS · Multi-part · Fermi University Physics · Mathematical Methods for Physics · Computational Physics · Monte Carlo and lattice simulation of physical systems
Error, Chance and the Machine, Ch Monte Carlo integration and variance reduction
Problem
Neutral particles are fired at normal incidence into a purely absorbing slab of thickness L=4 mean free paths ℓ. Each particle's free path is sampled by s=−ℓlnu with u uniform on (0,1); if s<L the particle is absorbed, otherwise it is transmitted. In a run of N=1×105 histories, nT=1832 particles are transmitted.
((a)) Give the estimated transmission fraction and its standard error, treating each history as a Bernoulli trial.
((b)) Compare with the analytic transmission e−L/ℓ and state whether the simulation is consistent with it.