Magnetic Multipole Field Generated by Columns of Permanent Magnets Arranged on a Cylindrical Surface

Abstract
The magnetic multipole field generated by columns of permanent magnets arranged on a cylindrical surface at equal intervals is calculated. Each magnet is replaced by two sheet currents flowing in opposite directions through each side of the magnet. The results have been compared with measured values and found to be in good agreement with them. These expressions are simple and very convenient for the design of a plasma source surrounded by magnetic multipole fields.