An RF Separator for Cloud Muons at TRIUMF

A particle separator utilizing a magnetic field crossed with an rf electric field has been built and incorporated into the M9 secondary channel to produce a clean negative muon beam at 77 MeV/c ± 5%. The separator is driven at the main cyclotron frequency (23 MHz) and phase locked to the primary proton beam. Separation is achieved by using both the temporal and velocity differences between the muons, produced near the production target (cloud muons), and both the pion and electron contaminants in the beam.