Free electron laser in magnetically dominated regime: simulations with ONEDFEL code

Maxim Lyutikov; Henry Freund

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arXiv · 2310.17028

Free electron laser in magnetically dominated regime: simulations with ONEDFEL code

Maxim Lyutikov·Henry Freund

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Abstract

Using the ONEDFEL code we perform Free Electron Laser simulations in the astrophysically important guide-field dominated regime. For wigglers' (Alfven waves) wavelengths of tens of meters and beam Lorentz factor $\sim 10^3$, the resulting coherently emitted waves are in the centimeter range. Our simulations show a growth of the wave intensity over fourteen orders of magnitude, over the astrophysically relevant scale of $\sim$ few kilometers. The signal grows from noise (unseeded). The resulting spectrum shows fine spectral sub-structures, reminiscent of the ones observed in Fast Radio Bursts (FRBs).

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Maxim Lyutikov, Henry Freund. 2023-10-25. Free electron laser in magnetically dominated regime: simulations with ONEDFEL code. https://arxiv.org/abs/2310.17028

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