# Compact buncher cavity for muons accelerated by a radio-frequency quadrupole

## TL;DR

This paper presents the design and successful operation of a compact radio-frequency buncher cavity for muons accelerated by an RFQ, achieving effective bunching within limited space constraints.

## Contribution

It introduces a novel double-gap TEM mode buncher cavity optimized for muon acceleration at 324 MHz with compact dimensions.

## Key findings

- Resonant frequency of 323.95 MHz achieved
- Unloaded quality factor of 3.06×10^3 measured
- Successfully used for muon bunch size measurement

## Abstract

A buncher cavity has been developed for the muons accelerated by a radio-frequency quadrupole linac (RFQ). The buncher cavity is designed for $\beta=v/c=0.04$ at an operational frequency of 324 MHz. It employs a double-gap structure operated in the TEM mode for the required effective voltage with compact dimensions, in order to account for the limited space of the experiment. The measured resonant frequency and unloaded quality factor are 323.95 MHz and $3.06\times10^3$, respectively. The buncher cavity was successfully operated for longitudinal bunch size measurement of the muons accelerated by the RFQ.