Digital Scholarship@UNLV

Title

Modeling, Fabrication, and Optimization of Niobium Cavities: Phase II Quarterly Report

Authors

Robert A. Schill Jr., University of Nevada, Las VegasFollow
Mohamed Trabia, University of Nevada, Las VegasFollow

Document Type

Report

Publication Date

9-1-2002

Publisher

University of Nevada, Las Vegas. Department of Mechanical Engineering.

Publisher Location

Las Vegas (Nev.)

First page number:

1

Last page number:

8

Abstract

Multipacting is one of the major loss mechanisms in rf superconductivity cavities for accelerators. This loss mechanism limits the maximum amount of energy/power supported by the cavities. Optimal designs have been identified in others’ studies. In practice, these designs are not easily manufactured. Chemical etching processes used to polish the cavity walls result in a nonuniform surface etch. A nonuniform surface etch will leave some unclean areas with contaminants and micron size particles. These significantly affect mutipacting. Further, a nonuniform etch will leave areas with damaged grain structure, which is not good for superconducting properties. Typically, the depth of chemical polishing etch ranges between 10 to 150 microns.

It is the purpose of this study to experimentally model the fluid flow resulting in the chemical etching of a niobium cavities with the aid of a baffle. Numerical tend to show that the current etching process with baffle does not uniformly etch the cavity surface. Multiple cavity cell geometries are to be investigated. Optimization techniques will be applied in search of the chemical etching processes, which will lead to cavity walls with near ideal properties.

Keywords

Elliptical cells; Holes; Linear accelerators; Niobium cavities; Niobium – Surfaces; Radio frequency; Resonant radio frequency; Surface preparation; Surfaces (Technology); Superconducting radio frequency; Superconductivity

Controlled Subject

Linear accelerators; Radio frequency; Superconductivity

Disciplines

Electrical and Computer Engineering | Mechanical Engineering | Metallurgy | Nuclear Engineering

File Format

pdf

File Size

484 KB

Language

English

Rights

IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/

Repository Citation

Schill, R. A., Trabia, M. (2002). Modeling, Fabrication, and Optimization of Niobium Cavities: Phase II Quarterly Report. 1-8.
Available at: https://digitalscholarship.unlv.edu/hrc_trp_sciences_materials/7