Laser-driven collimated tens-GeV monoenergetic protons from mass-limited target plus preformed channel

TL;DR

This paper demonstrates a method for laser-driven proton acceleration using a mass-limited target and preformed channel, achieving stable, collimated, monoenergetic protons exceeding 10 GeV in energy.

Contribution

The study introduces a novel target and channel configuration that enables stable, long-distance, high-energy proton acceleration with narrow divergence.

Findings

Achieved >10 GeV monoenergetic proton beam

Produced <2 degree divergence in proton beam

Demonstrated stable acceleration over long distances

Abstract

Proton acceleration by ultra-intense laser pulse irradiating a target with cross-section smaller than the laser spot size and connected to a parabolic density channel is investigated. The target splits the laser into two parallel propagating parts, which snowplow the back-side plasma electrons along their paths, creating two adjacent parallel wakes and an intense return current in the gap between them. The radiation-pressure pre-accelerated target protons trapped in the wake fields now undergo acceleration as well as collimation by the quasistatic wake electrostatic and magnetic fields. Particle-in-cell (PIC) simulation shows that stable long-distance acceleration can be realized, and a 30 fs monoenergetic ion beam of > 10 GeV peak energy and < 2degree divergence can be produced by a 9.8 *10^21 W/cm2 circularly polarized laser pulse.