Edge-Cooled, High-Current Septum Magnet

The resonant extraction system of the Zero Gradient Synchrotron (ZGS) includes a thin septum magnet with a two-turn winding having a total thickness of 0.06 in. The gap height is two in and the length is 20 in. This magnet is excited with currents as high as 7000 A (current density of 130,000 A/in2 to produce a field of 3.5 kG across the gap. Simplicity in design has been used extensively in the building of the core and the winding, resulting in an operation life test of one year to date. This magnet is used in a pulsed mode with a rise time of less than 100 ms and pulses up to 0. 8 s in length for slow spills. All portions of the design and fabrication are accomplished by taking advantage of commercially available materials and metals and no sophisticated machining practices were used in making this type of magnet. This paper describes the computer design, the construction practices, and the test data on pertinent parameters.