REAL-TIME BETATRON TUNE MEASUREMENT IN THE ACCELERATION RAMP AT COSY – JÜLICH

A new real-time method for betatron tune measure-ments at COSY was developed and tested from the early 1997. A bandlimited broadband noise source was used for beam excitation, the transversal beam position oscillation was bunch-synchronous sampled and digitized with a high resolution ADC. The Fourier transform of the acquired data represents immediately the betatron tune. After the first promising experiments an automatic tunemeter was constructed. The tunemeter is used as routine diagnostic tool since end of 1998.