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arXiv · 2608.04517

On the relationship between the gain of Stimulated Raman Backscatter of a short-pulse laser in a plasma and the Pierce parameter for XFELs

Xinlu Xu·Warren Mori
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Abstract

It is shown that the convective gain of Stimulated Raman Backscatter (SRBS) within a single laser wavelength in the strongly coupled regime is equivalent to the Pierce parameter commonly used to describe high gain x-ray Free Electron Lasers (XFELs). The comparison utilizes the fact that the gain is a Lorentz invariant so the Pierce parameter is written in terms of the FEL parameters in the electron beam's rest frame. It is thus inferred that there is a direct correspondence of the physics between SRBS in the strong-coupled regime and high gain XFELs in the Compton regime.

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Xinlu Xu, Warren Mori. 2026-08-05. On the relationship between the gain of Stimulated Raman Backscatter of a short-pulse laser in a plasma and the Pierce parameter for XFELs. https://arxiv.org/abs/2608.04517

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