Charged particle reflection in a magnetic mirror

Abstract

We study the reflection of electrons in a magnetic field mirror. It is a field with a gradient from a lowest value B₀ to a largest one B_m. With this purpose, Montecarlo simulations are made. We use a number of 5,000 particles with random pitch angles. The frequency distribution of these random values follows a Gaussian distribution centered at  \theta = 0 and with standard deviation \sigma. Various values of \sigma and also different values of the B₀ /B_m ratio are used in the simulations. The simulations show that \sigma has an important influence on the confinement of charged particles, for the different B₀ /B_m ratios here studied. However, the percent of reflected particles differs from a B₀ /B_m ratio to another in the whole range of \sigma, although for \sigma = 10 the differences between different ratios are small (<5%). The number of reflected particles increases very rapidly with \sigma, in the range of 10° to 40^°. For the \sigma range from 20^° to 40^°, the percent of reflected particles is \leq 20% larger for B₀ /B_m = 0.10 than for the 0.55 ratio.