Higher-order modes in the APS storage ring waveguides

Author

Brauer, S.O. ; Kustom, R.L.

Author_Institution

Adv. Photon Source, Argonne Nat. Lab., IL, USA

fYear

1993

fDate

17-20 May 1993

Firstpage

1217

Abstract

Twelve higher-order modes (HOMs) in the single-cell accelerating cavities for the Advanced Photon Source (APS) storage ring were calculated to have complex impedances that will cause coupled-bunched instabilities near or below the 300 mA positron current which is the design goal. Some of these modes couple, through the coupling loop, from the storage ring cavity into the waveguide. This study investigates the transmission of these modes from the cavity into the waveguide. The standing wave ratio (VSWR) of a WR2300 hybrid waveguide component has been measured at each HOM frequency, and its effect on the transmitted modes in the waveguide is studied

Keywords

cavity resonators; electron accelerators; particle beam diagnostics; storage rings; waveguide couplers; waveguides; 300 mA; APS storage ring waveguides; Advanced Photon Source; WR2300 hybrid waveguide component; coupled-bunched instabilities; higher-order modes; positron current; single-cell accelerating cavities; standing wave ratio; Damping; Electromagnetic waveguides; Impedance; Laboratories; Particle beams; Radio frequency; Shock absorbers; Stability; Storage rings; Threshold current;

fLanguage

English

Publisher

ieee

Conference_Titel

Particle Accelerator Conference, 1993., Proceedings of the 1993

Conference_Location

Washington, DC

Print_ISBN

0-7803-1203-1

Type

conf

DOI

10.1109/PAC.1993.308638

Filename

308638