A Fast Sequencing Bipolar Energy Discharge System for the Beam Bumper Magnet in the Zero Gradient Synchrotron

An energy discharge system has been constructed which permits repetitive pulses spaced 30 ms apart or greater to the Zero Gradient Synchrotron (ZGS) beam bumper magnet. To allow beam bumping to either side of the equilibrium orbit, each pulse is independent in polarity and magnitude. Two pulses per machine cycle are provided, but the system is being expanded to five. The system consists of the beam bumper magnet time-sharing two independent energy storage subsystems each containing two series ignitrons, one for each polarity and two crowbar ignitrons, one for each polarity. A logic system automatically triggers the crowbar associated with a given subsystem. An early crowbar trigger can be used which shunts the coil well before peak current occurs reducing the peak current on a given pulse. Each subsystem contains a 2 A, 14 kV power supply and 450 ¿F of capacitance. The beam bumper magnet has a 4-turn coil which may be connected either in parallel or series. The inductance for one turn is 1.6 ¿H. The beam may be targeted or extracted in less than 20 ¿s or as long as several hundred ¿s, depending on the choice of C and L. If exceptionally long times are needed, the subsystems may be interconnected causing all capacitors to be in parallel.