Geometric and Magnetic Measurements of the Gantry Dipole for the HICAT Medical Accelerator

Abstract

Part of the HICAT medical accelerator, under construction at Heidelberg, Germany, is a huge Gantry dipole. The magnet design was already reported at MT-17. This paper summarizes the main construction features. The geometric measurements are made with a laser tracker and include the determination of the iron core dimensions, the fiducialization and the alignment of the magnetic measurement equipment. Goal of the magnetic measurements was to shim the effective field boundary, to measure the integral field quality and the absolute integral field values. Dynamic field data in the central and in the fringe field are also reported.