The Experimental Program for High Pressure Gas Filled Radio Frequency Cavities for Muon Cooling Channels

TL;DR

This paper discusses the development and testing of high-pressure gas-filled RF cavities for muon cooling channels, crucial for future muon colliders and Higgs factories, highlighting experimental progress and technological advancements.

Contribution

It presents experimental results and technological developments of gas-filled RF cavities for muon cooling, advancing the feasibility of muon collider applications.

Findings

Progress in breakdown studies of RF cavities

Successful beam tests of cavity designs

Advancements in dielectric loaded and reentrant cavity technology

Abstract

An intense beam of muons is needed to provide a luminosity on the order of 10$^{34}$ cm$^{-2}$s$^{-1}$ for a multi-TeV collider. Because muons produced by colliding a multi-MW proton beam with a target made of carbon or mercury have a large phase space, significant six dimensional cooling is required. Through ionization cooling - the only cooling method that works within the lifetime of the muon - and emittance exchange, the desired emittances for a Higgs Factory or higher energy collider are attainable. A cooling channel utilizing gas filled radio frequency cavities has been designed to deliver the requisite cool muon beam. Technology development of these RF cavities has progressed from breakdown studies, through beam tests, to dielectric loaded and reentrant cavity designs. The results of these experiments are summarized.