Title :
Longitudinal coupled bunch instabilities on the NSLS X-ray ring
Author :
Klaffky, R.W. ; Broome, W. ; D´Alsace, R. ; Kramer, S.L. ; Thomas, M.G. ; Wang, J.M.
Author_Institution :
Nat. Synchrotron Light Source, Brookhaven Nat. Lab., Upton, NY, USA
Abstract :
Studies have demonstrated that an 862 MHz RF cavity higher order mode (HOM) causes longitudinal coupled-bunch (LCB) dipole and quadrupole oscillations at specific RF tuner positions with associated increases in longitudinal, horizontal, and vertical electron beam sizes. In the XRF2 cavity a reconfiguration of damping antennae removed the 862 MHz HOM. High speed I(t) stripline measurements showed that a strong quadrupole oscillation resulted when the HOM was induced in the XRF3 cavity. The reason that a symmetric six bunch pattern was found to be effective in damping this mode is explained
Keywords :
accelerator RF systems; accelerator cavities; electron accelerators; particle beam bunching; particle beam stability; storage rings; 862 MHz; NSLS; RF cavity; XRF2 cavity; XRF3 cavity; damping antennae; dipole oscillations; electron beam size; higher order mode; longitudinal coupled-bunch oscillations; quadrupole oscillations; Damping; Electron beams; Frequency measurement; Optical coupling; Position measurement; Radio frequency; Storage rings; Stripline; Synchrotrons; Tuners;
Conference_Titel :
Particle Accelerator Conference, 1997. Proceedings of the 1997
Conference_Location :
Vancouver, BC
Print_ISBN :
0-7803-4376-X
DOI :
10.1109/PAC.1997.751190
