A Cost-Effective Rapid-Cycling Synchrotron

TL;DR

This paper proposes a cost-effective rapid-cycling synchrotron design using a thin-wall metallic vacuum chamber, balancing the advantages and disadvantages of existing designs to optimize performance and cost.

Contribution

It introduces a novel RCS concept with a thin-wall metallic vacuum chamber as a compromise between cost and impedance issues.

Findings

Cost reduction compared to ceramic chamber designs

Reduced impedance issues relative to the original Fermilab Booster

Potential for improved performance and lower costs

Abstract

The present Fermilab proton Booster is an early example of a rapidly-cycling synchrotron (RCS). Built in the 1960s, it features a design in which the combined-function dipole magnets serve as vacuum chambers. Such a design is quite cost-effective, and it does not have the limitations associated with the eddy currents in a metallic vacuum chamber. However, an important drawback of that design is a high impedance, as seen by a beam, because of the magnet laminations. More recent RCS designs (e.g. J-PARC) employ large and complex ceramic vacuum chambers in order to mitigate the eddy current effects and to shield the beam from the magnet laminations. Such a design, albeit very successful, is quite costly because it requires large-bore magnets and large-bore RF cavities. In this article, we will consider an RCS concept with a thin-wall metallic vacuum chamber as a compromise between the chamber-less Fermilab Booster design and the large-bore design with ceramic chambers.