Simulations of Parametric Resonance Ionization Cooling of Muon Beams

Parametric-resonance ionization cooling (PIC) is being developed to create small beams so that high muon collider luminosity can be achieved with fewer muons. In the linear channel that is studied in this effort, a half integer resonance is induced such that the normal elliptical motion of particles in x − x′ phase space becomes hyperbolic, with particles moving to smaller x and larger x′ as they pass down the channel. Thin absorbers placed at the focal points of the channel then cool the angular divergence of the beam by the usual ionization cooling mechanism where each absorber is followed by RF cavities. Thus the phase space of the beam is compressed in transverse position by the dynamics of the resonance and its angular divergence is compressed by the ionization cooling mechanism. We report the first results of simulations of this process, a study of the compensation of chromatic aberration by using synchrotron oscillations.