Cold test measurements of a BWO slow-wave structure

Author

Main, W. ; Carmel, Y. ; Ogura, K. ; Weaver, J. ; Watanabe, S.

Author_Institution

Lab. for Plasma Res., Maryland Univ., College Park, MD, USA

fYear

1993

fDate

17-20 May 1993

Firstpage

2714

Abstract

Bead-on-string perturbation techniques have been primarily used to study particle accelerator cavities. These techniques are now extended to measure the dispersion relation and axial modes of several transverse magnetic (TM) modes in a slow-wave structure with sinusoidally varying radius. This type of slow-wave structure is commonly used in high power backward wave oscillators (BWO). The dispersion relation is found from the discrete measured resonant frequencies and wave numbers of a cavity containing six periods of the slow-wave structure. The measured axial and radial field profiles are compared with the results of a 2-D code specially developed for calculation of the fields in these generators. For the first three TM modes the frequency error was less than 0.7%

Keywords

backward wave tubes; cavity resonators; dispersion relations; microwave oscillators; 2D code; BWO slow-wave structure; TM modes; axial field profile; axial modes; bead-on-string perturbation techniques; cold test measurements; discrete measured resonant frequencies; dispersion relation; frequency error; high power backward wave oscillators; particle accelerator cavities; radial field profile; sinusoidally varying radius; transverse magnetic modes; wave numbers; Dispersion; Frequency measurement; Magnetic field measurement; Magnetic resonance; Microwave measurements; Numerical models; Oscillators; Plasma measurements; Resonant frequency; Testing;

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.1993.309438

Filename

309438