Control of focusing forces and emittances in plasma-based accelerators using near-hollow plasma channels

TL;DR

This paper proposes near-hollow plasma channels to independently control focusing and accelerating forces in plasma accelerators, enabling symmetric beam acceleration and reducing emittance growth for high-energy physics.

Contribution

Introduction of near-hollow plasma channels that decouple focusing and accelerating forces, improving control and beam quality in plasma-based accelerators.

Findings

Channels enable independent focusing and acceleration control.

Both electron and positron beams can be symmetrically accelerated.

Mitigation of emittance growth due to Coulomb scattering.

Abstract

A near-hollow plasma channel, where the plasma density in the channel is much less than the plasma density in the walls, is proposed to provide independent control over the focusing and accelerating forces in a plasma accelerator. In this geometry the low density in the channel contributes to the focusing forces, while the accelerating fields are determined by the high density in the channel walls. The channel also provides guiding for intense laser pulses used for wakefield excitation. In certain regimes, both electron and positron beams can be accelerated and focused in a nearly symmetric fashion. Near-hollow plasma channels can effectively mitigate emittance growth due to Coulomb scattering for high-energy physics applications.