Characterization of the Properties of a Ion Beam Steering Device

Subject area: Electricity & Magnetism -- application: Accelerator Physics, ion beam transport.

Teachers will measure the magnetic field distribution of a magnetic ion beam steerer as a function of excitation current and axial position. Additionally, using a time-varying current source, students will investigate the frequency response of the steerer. This project has direct application to the High Power Target Laboratory (HPTL) currently being constructed at the Holifield Facility. The data the students generate will determine the suitability of the device for use in delivering a beam from the Oak Ridge Isochronous Cyclotron (ORIC) to the HPTL target.

The steerer is set of coils wound around iron plates forming a box through which an ion beam pipe passes. The steerer is designed to provide a uniform magnetic field transverse to its axis (the beam pipe) and thus to provide steering in both x and y directions. It is currently in use on one of the high-energy beam lines at Holifield. Magnetic field measurements will be made with a Hall probe device (Group3 Teslameter) to determine the effective magnetic length of the steerer. Additionally, the central field will be measured as a function of excitation current. From these measurements, the teachers will calculate the deflection angle of a given ion beam as a function of current. Finally, the steerer power supply will be programmed with a frequency generator, and the output from the Hall probe will be observed on an oscilloscope to determine the frequency response of the steerer. The teachers will report on the capabilities of the steerer to provide raster scanning of an ion beam on the HPTL target.