Wake fields effects in dielectric capillary

TL;DR

This paper investigates how dielectric capillary structures influence wake fields in plasma acceleration, focusing on parameters affecting wake-field formation and their impact on beam stability in high-gradient acceleration schemes.

Contribution

It provides a quantitative analysis of how capillary dimensions and beam parameters affect wake-field amplitudes in dielectric structures for plasma acceleration.

Findings

Transverse wake fields can cause beam instability.

Capillary dimensions significantly influence wake-field strength.

Optimizing parameters reduces detrimental wake effects.

Abstract

Plasma wake-field acceleration experiments are performed at the SPARC LAB test facility by using a gas-filled capillary plasma source composed of a dielectric capillary. The electron can reach GeV energy in a few centimeters, with an accelerating gradient orders of magnitude larger than provided by conventional techniques. In this acceleration scheme, wake fields produced by passing electron beams through dielectric structures can determine a strong beam instability that represents an important hurdle towards the capability to focus high-current electron beams in the transverse plane. For these reasons, the estimation of the transverse wakefield amplitudes assumes a fundamental role in the implementation of the plasma wake-field acceleration. In this work, it presented a study to investigate which parameters affect the wake-field formation inside a cylindrical dielectric structure, both the capillary dimensions and the beam parameters, and it is introduced a quantitative evaluation of the longitudinal and transverse electric fields.