Beam halo from Touschek scattering in the KEK Accelerator Test Facility

TL;DR

This paper investigates beam halo formation in the KEK Accelerator Test Facility, identifying Touschek scattering as the main cause, through numerical simulations and experimental validation, to improve beam loss management.

Contribution

It provides combined numerical and experimental analysis of beam halo formation, highlighting Touschek scattering as the dominant mechanism in a high-intensity accelerator.

Findings

Numerical and experimental results show good agreement.

Touschek scattering is identified as the main cause of beam halo.

Insights can help improve beam loss suppression strategies.

Abstract

Beam halo is one of the crucial issues limiting the machine performance and causing radioactivation in high-intensity accelerators. A clear picture of beam-halo formation is of great importance for successful suppression of the undesired beam loss. We present numerical and experimental studies of transverse and longitudinal halos in the KEK Accelerator Test Facility. The fair accordance between predictions and observations in various conditions indicates that the Touschek scattering is the dominant mechanism forming the horizontal and momentum halos.