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arXiv · 2602.14734

An x-ray regenerative amplifier free-electron laser with a step-tapered-undulator

Henry P. Freund·P. J. M. van der Slot·P. G. O'Shea
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Abstract

Regenerative amplifier x-ray free-electron lasers constitute alternative configurations for fourth generation light sources which are typically operated in self-amplified spontaneous emission (SASE) mode. However, SASE exhibits relatively large fluctuations in the power and spectral properties from shot to shot, whereas XRAFELs provide a much more stable source of hard x-ray photons. Here, we study the performance of an x-ray cavity under consideration at the Stanford Linear Accelerator Facility using both uniform and step-tapered undulators with either transmissive or hole out-coupling.

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Henry P. Freund, P. J. M. van der Slot, P. G. O'Shea. 2026-02-16. An x-ray regenerative amplifier free-electron laser with a step-tapered-undulator. https://arxiv.org/abs/2602.14734

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