Book Description

Excerpt from The Motion of a Charged Particle in a Nearly Axisymmetric Magnetic Field The motion of a single charged particle in a given magnetic field, one of the first problems studied in plasma physics, (1) has recently become of interest again. Two topics of immediate significance in magnetic fusion energy research have sparked the current concernzlz) the confinement of high energy alpha particles and the drift motion of moderate energy particles induced by small magnetic fields that break axial symmetry. The large body of older theory has been used to provide a base for extensive numerical computations. Here, we examine the problemiwith analytic tools to discover what improved descriptions of single particle motion we are able to provide. The critical concept in the study of the single particle dynamics is the existence of adiabatic invariants of the motion which allows great simplifications in the study of the dynamics. The adiabatic invariants are associated with the presence of a physical parameter which is small, the ratio of the larmor radius to the characteristic distance over which magnetic fields vary; and we denote this parameter by 6. Unlike the earlier treatments we assume that parts of the axisymmetric magnetic field may be small in e and we also take the symmetry breaking field to be small in e. Not surprisingly, we find that these assumptions do allow considerably more analysis than is possible without them. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.