Title :
Beam echoes in the CERN SPS
Author :
Bruning, O. ; Linnecar, T. ; Ruggiero, E. ; Scandale, W. ; Shaposhnikova, E. ; Stellfeld, D.
Author_Institution :
CERN, Geneva, Switzerland
Abstract :
Longitudinal echo signals have been produced in the CERN SPS by exciting a proton beam at 120 GeV/c with two short RF pulses separated by a suitable time-delay. The aim of the experiments was to confirm the analytical predictions for beam echoes in the SPS and to probe the applicability of beam echoes for a measurement of the energy distribution and diffusion coefficients in the accelerator. We summarise here the results obtained with bunched and unbunched beams. For an unbunched beam, the excitation frequencies are at different harmonics of the revolution frequency and result in an echo response at the difference frequency of the two RF kicks. For the case of a bunched beam, the RF kicks are adjusted to excite the quadrupole mode of the bunch motion and the beam echo response can also be observed as a quadrupole mode
Keywords :
particle beam diagnostics; particle beam dynamics; proton accelerators; proton beams; storage rings; synchrotrons; CERN SPS; RF kicks; beam echoes; bunch motion; bunched beams; diffusion coefficients; energy distribution; longitudinal echo signals; proton beam; quadrupole mode; short RF pulses; unbunched beams; Delay effects; Energy measurement; Equations; Noise level; Noise measurement; Noise reduction; Pulse measurements; Radio frequency; Switches; Time measurement;
Conference_Titel :
Particle Accelerator Conference, 1997. Proceedings of the 1997
Conference_Location :
Vancouver, BC
Print_ISBN :
0-7803-4376-X
DOI :
10.1109/PAC.1997.751027
