Document Type

Annual Report

Publication Date



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

Publisher Location

Las Vegas (Nev.)

First page number:


Last page number:



One of the key technologies for the deployment of acceleratordriven transmutation systems is the accelerator itself. Elliptical superconducting niobium cavities are used to increase the efficiency of the high-power accelerators needed to support the transmutation mission.

One of the major sources of energy loss from a superconducting accelerator cavity is a process known as multiple impacting (or “multipacting”) of electrons. This phenomenon limits the maximum amount of energy and power that the niobium cavity can store. As a result, the maximum power available for accelerating the desired charge, as well as the overall performance of the accelerator is reduced. Furthermore, the energy absorbed as a result of multipacting eventually turns into heat. This negatively impacts the performance of both the superconducting cavity and the accelerator.

This project is tasked with examining the impacts of the design and fabrication technologies for these elliptical niobium cavities on their performance. Niobium was selected primarily due to its behavior at low temperatures.

One objective of this study is to experimentally model the fluid flow resulting in the chemical etching of a niobium cavities with the aid of a baffle. Numerical analyses 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.

Modeling codes, optimization techniques, and experimentation will provide UNLV researchers with a well-rounded study to examine existing and novel niobium cavity designs for the superconducting radio frequency high-current accelerator.


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


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

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176 KB




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