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arXiv · 2306.16590

Nonlinearly Shaped Pulses in Photoinjectors and Free-Electron Lasers

Nicole Neveu·Randy Lemons·Joseph Duris·Jingyi Tang·Yuantao Ding·Agostino Marinelli·Sergio Carbajo
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Abstract

Photoinjectors and Free Electron Lasers (FEL) are amongst the most advanced systems in accelerator physics and have consistently pushed the boundaries of emittance and x-ray peak power. In this paper, laser shaping at the cathode is proposed to further lower the emittance and reduce electron beam tails, which would result in brighter x-ray production. Using dispersion controlled nonlinear shaping (DCNS), laser pulses and beam dynamics were simulated in LCLS-II. The photoinjector emittance was optimized and the resulting e-beam profiles were then simulated and optimized in the linac. Finally, the expected FEL performance is estimated and compared to the current technology: Gaussian laser pulses on the cathode. The e-beams produced by DCNS pulses show a potential for 35% increase in x-ray power per pulse during SASE when compared to the standard Gaussian laser pulses.

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Nicole Neveu, Randy Lemons, Joseph Duris, Jingyi Tang, Yuantao Ding, Agostino Marinelli, Sergio Carbajo. 2023-06-28. Nonlinearly Shaped Pulses in Photoinjectors and Free-Electron Lasers. https://arxiv.org/abs/2306.16590

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