Title :
Longitudinal and transverse feedback systems for PLS storage ring
Author :
Kang, H.S. ; Hwang, W.H. ; Park, H.-J. ; Kim, D.T. ; Huang, J.-Y. ; Nam, S.H.
Author_Institution :
Pohang Accelerator Lab., Kyungbuk, South Korea
fDate :
6/23/1905 12:00:00 AM
Abstract :
The Pohang Light Source (PLS) storage ring uses two bunch-by-bunch feedback systems - a longitudinal feedback system (LFS) and a transverse feedback system (TFS) - to cure the coupled bunch instabilities due to higher order modes of RF cavities and resistive wall impedance. The LFS employs the digital electronics developed for ALS and PEPII and uses a cavity-type kicker, and it was successfully commissioned in 1999 with the aid of SLAC. The TFS uses analog two-tap coaxial notch filters for the closed orbit offset signal rejection. The TFS is now in upgrade to use one kicker per transverse plane to improve efficiency over the previous system with a kicker combining both planes in a single structure. This paper will describe the achieved results of curing the coupled bunch instabilities by using the LFS and TFS together with current status
Keywords :
X-ray production; accelerator RF systems; accelerator cavities; accelerator magnets; electromagnets; electron accelerators; electron beams; notch filters; nuclear electronics; particle beam bunching; particle beam extraction; particle beam stability; storage rings; LFS; PLS storage ring; Pohang Light Source; beam currents; beam emittance; bunch instability; bunch-by-bunch feedback systems; cavity-type kicker; closed orbit offset signal rejection; coaxial notch filters; coupled bunch instabilities; digital electronics; higher order modes; longitudinal feedback systems; radiofrequency cavities; resistive wall impedance; transverse feedback systems; Current measurement; Feedback; Filters; Impedance; Light sources; Optical coupling; Radio frequency; Sampling methods; Storage rings; Tuning;
Conference_Titel :
Particle Accelerator Conference, 2001. PAC 2001. Proceedings of the 2001
Print_ISBN :
0-7803-7191-7
DOI :
10.1109/PAC.2001.986766
