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arXiv · 2512.21212

Study of laser-beam arrival time synchronization towards sub-picosecond stability level

Konstantin Popov·Hiroshi Kaji·Tetsuya Kobayashi·Aurelien Martens·Daniel Charlet·Cedric Esnault·Antoine Back·Paul-Eric Pottie·Fabian Zomer·Alexander Aryshev
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Abstract

A precise synchronization between laser pulse and electron beam arrival time is essential for achieving sub-picosecond stability in modern accelerator facilities. In this work, a Low-Level RF system architecture combined with White Rabbit based timing system has been tested through a collaboration between KEK (Japan) and CNRS/IN2P3, IJClab (France). The setup combines a frequency standard generator, an IDROGEN carrier board with an embedded White Rabbit node, and SkyWorks synthesizers of different form factors to distribute phase-locked clock signals over telecommunication fiber. Phase noise power spectral density measurements were performed at several RF sub-harmonics to confirm synchronization performance. These results demonstrate the feasibility of implementing the White Rabbit-IDROGEN synchronization scheme for large-scale accelerators, including applications to laser-based diagnostics.

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Konstantin Popov, Hiroshi Kaji, Tetsuya Kobayashi, Aurelien Martens, Daniel Charlet, Cedric Esnault, Antoine Back, Paul-Eric Pottie, Fabian Zomer, Alexander Aryshev. 2025-12-24. Study of laser-beam arrival time synchronization towards sub-picosecond stability level. https://arxiv.org/abs/2512.21212

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