Title :
Measurement of longitudinal instability threshold in the PF-AR
Author :
Ieiri, Takao ; Obina, Takashi
Author_Institution :
KEK, Ibaraki, Japan
Abstract :
A single bunch longitudinal instability was experimentally investigated in the PF-AR under the condition that the number of cavity-cell which greatly contributed to longitudinal impedance was changed. The bunch length was measured as a function of the bunch current. Hysteresis phenomena in bunch lengthening process were discovered in the former condition of fully installed cavities. The present condition of reduced cavity-cells to 3/4 indicated an abrupt increase of the bunch length together with the energy spread at a bunch current. The instability threshold current was measured as a function of the bunch length. Measured results are consistent with Oide´s criterion
Keywords :
electron accelerators; particle beam bunching; particle beam diagnostics; particle beam stability; storage rings; Oide´s criterion; PF-AR; bunch current; bunch lengthening process; hysteresis phenomena; instability threshold current; longitudinal impedance; single bunch longitudinal instability threshold measurement; Acceleration; Bellows; Current measurement; Distortion measurement; Hysteresis; Impedance; Length measurement; Storage rings; Virtual colonoscopy; Voltage;
Conference_Titel :
Particle Accelerator Conference, 1999. Proceedings of the 1999
Conference_Location :
New York, NY
Print_ISBN :
0-7803-5573-3
DOI :
10.1109/PAC.1999.795473
