Beam Loss and Average Beam Current Measurements Using a CWCT

The CWCT is a novel instrument adapted to an accurate average current determination of bunched CW beams or macro pulses. By combining a high-droop current transformer with novel electronics for signal analysis, an output signal bandwidth of DC to about 500kHz and a current resolution down to the micro-ampere level are achieved. Beam current fluctuations are followed within microseconds, permitting fast detection of beam loss. These characteristics render the CWCT an ideal instrument for HPPAs, for example ADS linacs, and other proton or ion accelerators. We present the CWCT principle and the CWCT performance achieved in beam experiments at UNILAC, GSI.