Betatron “Ping” tune measurement system for the IUCF cooler synchrotron/storage ring

A system has been developed for nearly real-time measurement of the coherent betatron fractional tune, ΔQ, in the IUCF cooler synchrotron/storage ring. This system measures the horizontal and vertical beam position on a turn-by-turn basis for beam currents in the range from <1 μA to >1 mA. A fast Fourier transform of this position data is performed by a PC-based DSP module at a rate of 10 measurements per second yielding the betatron fractional tune. This tune information has been used to modify ramp parameters in order to minimize the tune shift. This paper describes the ping tune system´s overall design principles, details of the various electronics systems, and compares the theoretical performance with the measured performance