Rapid-cycling synchrotron with variable momentum compaction

TL;DR

This paper proposes a lattice design with a variable momentum compaction factor for a rapid-cycling synchrotron, addressing conflicting energy ramping requirements in high-energy particle accelerators.

Contribution

It introduces a novel lattice design with variable momentum compaction, enabling better control during energy ramping in synchrotrons for muon colliders and neutrino factories.

Findings

Design feasibility of variable momentum compaction lattice

Potential for improved energy ramping efficiency

Application to high repetition rate proton drivers

Abstract

There are conflicting requirements on the value of the momentum compaction factor during energy ramping in a synchrotron: at low energies it should be positive and sufficiently large to make the slippage factor small so that it is possible to work closer to the RF voltage crest and ensure sufficient RF bucket area, whereas at higher energies it should be small or negative to avoid transition crossing. In the present report we propose a lattice with a variable momentum compaction factor and consider the possibility of using it in a high repetition rate proton driver for a muon collider and neutrino factory.