Magnetic Field Measurement and Spectroscopy in Multipole Fields

The magnetic field measurements in multipole magnetic fields, which are used to measure magnetic field parameters in the strong-focusing lenses for the Stanford two-mile linear accelerator, will be reviewed. Specifically, the theory and the measurement processes used to determine such important parameters as the magnetic center in multipoles, the length of the gradient fields, and the harmonic content in strong-focusing lenses will be described. The results of these accurate measurements will be related to the optical parameters of the multipole lenses.