Title :
Impedance calculations for 2-D and 3-D structures and the impedance budget of 7-GeV APS storage ring
Author :
Chou, W. ; Jin, Y.
Author_Institution :
Argonne Nat. Lab., IL, USA
Abstract :
The longitudinal and transverse coupling impedances of various kinds of two- and three-dimensional structures are calculated numerically for the storage ring of the 7-GeV Advanced Photon Source (APS). It is shown that the RF cavities are the main contributors to the longitudinal impedance, whereas the transitions between the chamber and the insertion device section dominate the transverse impedances. Several different numerical approaches are adopted. It is argued that the broadband resonator model may not be appropriate for modeling the longitudinal impedance. Several interesting phenomena of general interest, including a composition rule and the negative transverse impedance, are discussed. The present results and other results available are used to establish the impedance budget of the storage ring
Keywords :
beam handling equipment; beam handling techniques; electric impedance; storage rings; APS storage ring; RF cavities; broadband resonator model; composition rule; impedance budget; insertion device; longitudinal impedance; negative transverse impedance; three-dimensional structures; transverse coupling impedances; two-dimensional structures; Bellows; Computational geometry; Computer simulation; Impedance; Laboratories; Particle beams; Radio frequency; Storage rings; Valves; Welding;
Conference_Titel :
Particle Accelerator Conference, 1989. Accelerator Science and Technology., Proceedings of the 1989 IEEE
Conference_Location :
Chicago, IL
DOI :
10.1109/PAC.1989.73274
