A fully automated electrolytic tank system and its use in cyclotron injection studies

Abstract

A fully automated electrolytic tank analog system was built at the University of Maryland. This facility was used in central-region design studies for the University's sector-focused cyclotron, which is now under construction, and for similar studies by several other cyclotron laboratories. Main features of the facility are motor-controlled x, y positioning slides and a preset indexer system for automated probe motion, a self-balancing bridge and digital volmeter measuring the potential at incremental steps, and a teletypewriter recording the data values. The electric potential distribution is measured in a scaled tank mockup of the electrode geometry at the cyclotron center and carried as a two-dimensional grid of data points. Grid size and incremental step with are adjustable within wide limits. The tank box with electrolyte (distilled water in this case) and electrode system is a separate unit mounted on an alignment table and can easily be replaced by other mockup structures. The recorded data, punched on paper tape, is used for calculations with the digital computer. A program called HOUNDOG permits the calculation and plotting (with a Calcomp unit) of equipotential lines. Ion trajectories are calculated and plotted with the PINWHEEL program. Magnetic field information for PINWHEEL was obtained from model magnet measurements or from theoretically determined field shapes. Some typical results of the central-orbit studies for the Maryland cyclotron are presented.