Spatiotemporal dynamics of ultrarelativistic beam-plasma instabilities
Abstract
An electron or electron-positron beam streaming through a plasma is notoriously prone to micro-instabilities. For a dilute ultrarelativistic infinite beam, the dominant instability is a mixed mode between longitudinal two-stream and transverse filamentation modes, with a phase velocity oblique to the beam velocity. A spatiotemporal theory describing the linear growth of this oblique mixed instability is proposed, which predicts that spatiotemporal effects generally prevail for finite-length beams, leading to a significantly slower instability evolution than in the usually assumed purely temporal regime. These results are accurately supported by particle-in-cell (PIC) simulations. Furthermore, we show that the self-focusing dynamics caused by the plasma wakefields driven by finite-width beams can compete with the oblique instability. Analyzed through PIC simulations, the interplay of these two processes in realistic systems bears important implications for upcoming accelerator experiments on ultrarelativistic beam-plasma interactions.
Keywords
Cite
@article{arxiv.2106.11625,
title = {Spatiotemporal dynamics of ultrarelativistic beam-plasma instabilities},
author = {P. San Miguel Claveria and X. Davoine and J. R. Peterson and M. Gilljohann and I. Andriyash and R. Ariniello and H. Ekerfelt and C. Emma and J. Faure and S. Gessner and M. Hogan and C. Joshi and C. H. Keitel and A. Knetsch and O. Kononenko and M. Litos and Y. Mankovska and K. Marsh and A. Matheron and Z. Nie and B. O'Shea and D. Storey and N. Vafaei-Najafabadi and Y. Wu and X. Xu and J. Yan and C. Zhang and M. Tamburini and F. Fiuza and L. Gremillet and S. Corde},
journal= {arXiv preprint arXiv:2106.11625},
year = {2022}
}