Error analysis and lattice improvement for the C-ADS Injector-I

TL;DR

This paper analyzes errors in the C-ADS Injector-I, designs an orbit correction scheme, and proposes an improved lattice to minimize beam loss in a proton linac.

Contribution

It provides a comprehensive error analysis, an orbit correction method, and an improved lattice design for the C-ADS Injector-I.

Findings

Residual orbit errors controlled within 0.3 mm

Beam loss rate reduced to 1.7×10^-6 with correction

Improved lattice design further reduces beam loss

Abstract

The injector (Scheme-I) of the C-ADS linac is a 10-mA 10-MeV proton linac working in CW mode. It is mainly comprised of a 3.2-MeV room-temperature 4-vane RFQ and twelve superconducting single-spoke cavities housed in a long cryostat. Error analysis including alignment and field errors, static and dynamic ones for the injector are presented. Based on detailed numerical simulations, an orbit correction scheme has been designed. It shows that with correction the rms residual orbit errors can be controlled within 0.3 mm and a beam loss rate of 1.7*10^-6 is obtained. To reduce the beam loss rate further, an improved lattice design for the superconducting spoke cavity section has been studied.