Two-stage laser acceleration of high quality protons using a tailored density plasma

Y Wan,I A Andriyash,W Lu,C Joshi,V Malka,C.-H Pai,J F Hua,W B Mori

doi:10.1103/physrevaccelbeams.22.021301

Abstract

A new scheme of proton acceleration from a laser-driven near-critical-density plasma is proposed. Plasma with a tailored density profile allows a two-stage acceleration of protons. The protons are pre-accelerated in the laser-driven wakefields, and are then further accelerated by the collisionless shock, launched from the rear side of the plasma. The shock has a small transverse size, and it generates a strong space-charge field, which defocuses protons in such a way, that only those protons with the highest energies and low energy spread remains collimated. Theoretical and numerical analysis demonstrates production of high-energy proton beams with few tens of percents energy spread, few degrees divergence and charge of few nC. This scheme indicates the efficient generation of quasi-monoenergetic proton beams with energies up to several hundreds of MeV with PW-class ultrashort lasers.

Highlights

Over the past decades, many new exciting applications of the interactions of ultraintense lasers with matter have been developed [1]
The designed plasma profile allows for the laser channeling of the dense plasma, which triggers a two-stage acceleration of protons—first accelerated by the laser acting as a snowplow in plasma, and by the collisionless shock launched from the sharp density downramp
With a PW-class ultrashort laser this scheme predicts the generation of such high quality proton beams with energies up to several hundreds of MeV

Summary

Introduction

Many new exciting applications of the interactions of ultraintense lasers with matter have been developed [1]. Two-stage laser acceleration of high quality protons using a tailored density plasma

Results

Conclusion