J. A. Maloney | Searcharxiv

arXiv2014

Numerical Studies of Optimization and Aberration Correction Methods for the Preliminary Demonstration of the Parametric Ionization Cooling (PIC) Principle in the Twin Helix Muon Cooling Channel

Muon colliders have been proposed for the next generation of particle accelerators that study high-energy physics at the energy and intensity frontiers. In this paper we study a possible implementation of muon ionization cooling, Parametric-resonance Ionization Cooling (PIC), in the twin helix channel. The resonant cooling method of PIC offers the potential to reduce emittance beyond that achievable with ionization cooling with ordinary magnetic focusing. We examine optimization of a variety of parameters, study the nonlinear dynamics in the twin helix channel and consider possible methods of aberration correction.

physics.acc-ph↗

arXiv2012

Parametric-resonance Ionization Cooling of Muon Beams

Cooling of muon beams for the next-generation lepton collider is necessary to achieve its higher luminosity with fewer muons. In this paper we present an idea to combine ionization cooling with parametric resonances that is expected to lead to muon beams with much smaller transverse sizes. We describe a linear magnetic transport channel where 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' at the channel focal points. 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. We present a theory of Parametric-resonance Ionization Cooling (PIC), starting with the basic principles in the context of a simple quadrupole-focused beam line. Then we discuss detuning caused by chromatic, spherical, and non-linear field aberrations and the techniques needed to reduce the detuning. We discuss the requirement that PIC be accompanied by emittance exchange in order to keep the momentum spread sufficiently small. Examples of PIC channel are presented, along with computer simulations aimed at practical implementation of the described theoretical concept.

physics.acc-ph↗