Evolution of the self-injection process in the transition of an LWFA from self-modulation to blowout regime

Prabhat Kumar; Kwangmin Yu; Rafal Zgadzaj; Michael Downer; Irina Petrushina; Roman Samulyak; Vladimir Litvinenko; Navid Vafaei-Najafabadi

doi:10.1063/5.0027167

arXiv · 2008.12157

Evolution of the self-injection process in the transition of an LWFA from self-modulation to blowout regime

Prabhat Kumar·Kwangmin Yu·Rafal Zgadzaj·Michael Downer·Irina Petrushina·Roman Samulyak·Vladimir Litvinenko·Navid Vafaei-Najafabadi

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Abstract

Long wavelength infrared (LWIR) laser driven plasma wakefield accelerators are investigated here in the self-modulated laser wakefield acceleration (SM-LWFA) and blowout regimes using 3D Particle-in-Cell simulations. The simulation results show that in SM-LWFA regime, self-injection arises with wave breaking, whereas in the blowout regime, self-injection is not observed under the simulation conditions. The wave breaking process in SM-LWFA regime occurs at a field strength that is significantly below the 1D wave-breaking threshold. This process intensifies at higher laser power and plasma density and is suppressed at low plasma densities ($\leq 1\times10^{17}$ $cm^{-3}$ here). The produced electrons show spatial modulations with a period matching that of the laser wavelength, which is a clear signature of direct laser acceleration (DLA).

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Prabhat Kumar, Kwangmin Yu, Rafal Zgadzaj, Michael Downer, Irina Petrushina, Roman Samulyak, Vladimir Litvinenko, Navid Vafaei-Najafabadi. 2020-08-27. Evolution of the self-injection process in the transition of an LWFA from self-modulation to blowout regime. https://doi.org/10.1063/5.0027167

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