Effect of Dielectric Wakefields in a Capillary Discharge for Plasma Wakefield Acceleration

TL;DR

This paper investigates how dielectric wakefields in capillary discharges affect beam trajectory and wakefield decay, providing insights for optimizing plasma wakefield accelerators using dielectric capillaries.

Contribution

It presents experimental measurements of beam deflection and wakefield decay in dielectric capillaries, highlighting effects of misalignment and bunch position for accelerator design.

Findings

Deflection increases with bunch length and misalignment.

Wakefield effects decay along the bunch.

Implications for designing dielectric-based plasma accelerators.

Abstract

Dielectric capillaries are widely used to generate plasmas for plasma wakefield acceleration. When a relativistic drive bunch travels through a capillary with misaligned trajectory with respect to the capillary axis, it is deflected by the effect of the dielectric transverse wakefields it drives. We experimentally show that the deflection effect increases along the bunch and with larger misalignment, and we investigate the decay of dielectric wakefields by measuring the effect on the front of a trailing bunch. We discuss the implications for the design of a plasma wakefield accelerator based on dielectric capillaries.