# MACH - a computer code for solution of the poloidal asymmetry eigenvalue problem in tokamaks

## Description

Abstract Evaluation of the poloidal dependence of the plasma density involves solving the equation for momentum balance along the magnetic field. This is transformed into an eigenvalue equation of the Mathieu type with an extra damping term. The method presented here for determination of the appropriate eigenvalue is much faster than traditional matrix determinant methods. Title of program: MACH Catalogue Id: ACPY_v1_0 Nature of problem The ions in a tokamak plasma gyrate around and stream along magnetic field lines that encircle the torus in both the poloidal (short- circumference) and toroidal (long circumference) directions. In the infinite aspect ratio limit, the geometry is cylindrical and the plasma ion density is poloidally symmetric, but at finite aspect ratios the symmetry is broken. Given a poloidal "Mach number" that is related to the plasma rotation velocity, the poloidal variation of the plasma density is determine ... Versions of this program held in the CPC repository in Mendeley Data ACPY_v1_0; MACH; 10.1016/0010-4655(94)90077-9 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)