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arXiv · 2503.00899

Zeptosecond Gamma-Ray Pulses Generation via FEL-Driven Microbunching and Laser-Compton Scattering

Jinke Xiong·Hanghua Xu·Liangliang Ji·Chao Feng
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Abstract

We introduce a novel and reliable approach to generate zeptosecond(10^{-21} s,zs), high-energy photon pulse bursts by synergistically exploiting the inherent characteristics of Free-Electron Lasers (FELs) and laser-Compton scattering. The feasibility of this scheme is validated through comprehensive numerical simulations. In a representative simulation, a 4 GeV electron beam, undergoing the FEL process, emits radiation at 0.7 nm and develops a microbunched structure. These microbunches subsequently interact with a 2 ps, 9 micrometers laser pulse in a head-on Compton scattering configuration. Our simulation results demonstrate that under conditions of well-established electron beam microbunching, the proposed method successfully yields high-brightness gamma-photon pulse bursts with durations approaching 800 zeptoseconds and exhibiting exceptional signal-to-noise ratios, consistent with theoretical expectations. This technique opens up avenues for exploring ultrafast nuclear dynamics and provides unprecedented perspectives for delving into the Quantum Zeno and Anti-Zeno effects.

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Jinke Xiong, Hanghua Xu, Liangliang Ji, Chao Feng. 2025-03-02. Zeptosecond Gamma-Ray Pulses Generation via FEL-Driven Microbunching and Laser-Compton Scattering. https://arxiv.org/abs/2503.00899

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