Low divergence proton beams from a laser-plasma accelerator at kHz repetition rate

• Main Authors: Levy, Dan, Andriyash, Igor A, Haessler, Stefan, Ouillé, Marie, Kaur, Jaismeen, Flacco, Alessandro, Kroupp, Eyal, Malka, Victor, Lopez-Martens, Rodrigo
• Format: Journal Article
• Language: English
• Published: 12-07-2022
• Subjects: Physics - Accelerator Physics; Physics - Plasma Physics
• DOI: 10.48550/arxiv.2112.12581

Proton beams with up to 100 pC bunch charge, 0.48 MeV cut-off energy and
divergence as low as a $3^{\circ}$ were generated from solid targets at kHz
repetition rate by a few-mJ femtosecond laser under controlled plasma
conditions. The beam spatial profile was measured using a small aperture
scanning time-of-flight detector. Detailed parametric studies were performed by
varying the surface plasma scale length from 8 to 80 nm and the laser pulse
duration from 4 fs to 1.5 ps. Numerical simulations are in good agreement with
observations and, together with an in-depth theoretical analysis of the
acceleration mechanism, indicate that high repetition rate femtosecond laser
technology could be used to produce few-MeV protons beams for applications.