CHART - a program for solving the neutron transport equation in cylindrical and spherical geometries using a characteristics formulation

A characteristics formulation of the neutron transport equation leads to rather simple finite difference equations, which can be conveniently applied to a wide range of geometries. The program CHART has been written to apply the characteristics method to one dimensional cylindrical and spherical systems. The paper outlines the theoretical methods used in its development, and gives details necessary for running the program in conjunction with the WIMS-E modular scheme. A brief comparison with alternative methods is also included. (author)