Enhanced electron yield from a laser-plasma accelerator using high-Z gas jet targets

TL;DR

This study compares electron beam yields from different gas jet targets in laser-plasma acceleration, demonstrating that high-Z gases like argon produce significantly higher charge due to cluster formation, enhancing electron yield.

Contribution

It provides the first detailed comparison of electron yields from low-Z and high-Z gas jets, highlighting the role of cluster formation in high-Z gases for improved electron acceleration.

Findings

High-Z gases produce higher electron yields than low-Z gases.

Cluster formation in high-Z gases correlates with increased electron charge.

Argon gas jets achieved up to ~3 nC electron charge.

Abstract

An investigation of the multi-hundred MeV electron beam yield (charge) form helium, nitrogen, neon and argon gas jet plasmas in a laser-plasma wakefield acceleration experiment was carried out. The charge measurement has been made via imaging the electron beam intensity profile on a fluorescent screen into a 14-bit charge coupled device (CCD) which was cross-calibrated with nondestructive electronics-based method. Within given laser and plasma parameters, we found that laser-driven low Z- gas jet targets generate high-quality and well-collimated electron beams with reasonable yields at the level of 10-100 pC. On the other hand, filamentary electron beams which were observed from high-Z gas jets at higher densities reached much higher yield. Evidences for cluster formation were clearly observed in high-Z gases, especially in the argon gas jet target where we received the highest yield of ~ 3 nC