Effect of geometric azimuthal asymmetries of PPM stack on electron beam characteristics [TWTs]

Author

Kory, Carol L.

Author_Institution

NASA Glenn Res. Center, Analex Corp., Cleveland, OH, USA

Volume

48

Issue

1

fYear

2001

fDate

1/1/2001 12:00:00 AM

Firstpage

38

Lastpage

44

Abstract

A three-dimensional (3-D) beam optics model has been developed using the electromagnetic particle-in-cell (PIC) code MAFIA. The model includes an electron beam with initial transverse velocity distribution focused by a periodic permanent magnet (PPM) stack. All components of the model are simulated in three dimensions, allowing several azimuthally asymmetric traveling wave tube (TWT) characteristics to be investigated for the first time. These include C-magnets, shunts and magnet misalignment and their effects on electron beam behavior. The development of the model is presented and 3-D TWT electron beam characteristics are compared in the absence of and under the influence of the azimuthally asymmetric characteristics described

Keywords

digital simulation; electron optics; permanent magnets; travelling wave tubes; C-magnets; MAFIA; PPM stack; beam optics model; electromagnetic particle-in-cell code; electron beam behavior; electron beam characteristics; geometric azimuthal asymmetries; initial transverse velocity distribution; magnet misalignment; periodic permanent magnet; shunts; traveling wave tube; Circuits; Electron beams; Electron optics; Integrated optics; Magnetic flux; Magnetostatics; Optical beams; Optical scattering; Permanent magnets; Solid modeling;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.892165

Filename

892165