First muon acceleration using a radio-frequency accelerator

Abstract

Muons have been accelerated by using a radio-frequency accelerator for the first time. Negative muonium atoms (Mu(-)), which are bound states of positive muons (mu(+)) and two electrons, are generated from is mu(+)'s through the electron capture process in an aluminum degrader. The generated Mu(-) 's are initially electrostatically accelerated and injected into a radio-frequency quadrupole linac (RFQ). In the RFQ, the Mu 's are accelerated to 89 keV. The accelerated Mu(-) 's are identified by momentum measurement and time of flight. This compact muon linac opens the door to various muon accelerator applications including particle physics measurements and the construction of a transmission muon microscope.