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arXiv · 2410.21309

Differential pumping for kHz operation of a Laser Wakefield accelerator based on a continuously flowing Hydrogen gas jet

Joséphine Monzac·Slava Smartsev·Julius Huijts·Lucas Rovige·Igor A. Andriyash·Aline Vernier·Vidmantas Tomkus·Valdas Girdauskas·Gediminas Raciukaitis·Miglė Mackevičiūtė·Valdemar Stankevic·Antoine Cavagna·Jaismeen Kaur·André Kalouguine·Rodrigo Lopez-Martens·Jérôme Faure
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Abstract

Laser-Wakefield Accelerators (LWFA) running at kHz repetition rates hold great potential for applications. They typically operate with low-energy, highly compressed laser pulses focused in high-pressure gas targets. Experiments have shown that the best-quality electron beams are achieved using Hydrogen gas targets. However, continuous operation with Hydrogen requires a dedicated pumping system. In this work, we present a method for designing a differential pumping system, which we successfully implemented in our experiments. This enabled the first demonstration of continuous operation of a kHz LWFA using a high-pressure Hydrogen gas jet. The system effectively maintained a pressure below 3e-4 mbar, even with a free-flowing gas jet operating at 140 bar backing pressure. Numerical fluid dynamics and optical simulations were used to guide and validate the system's design.

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Joséphine Monzac, Slava Smartsev, Julius Huijts, Lucas Rovige, Igor A. Andriyash, Aline Vernier, Vidmantas Tomkus, Valdas Girdauskas, Gediminas Raciukaitis, Miglė Mackevičiūtė, Valdemar Stankevic, Antoine Cavagna, Jaismeen Kaur, André Kalouguine, Rodrigo Lopez-Martens, Jérôme Faure. 2024-10-25. Differential pumping for kHz operation of a Laser Wakefield accelerator based on a continuously flowing Hydrogen gas jet. https://arxiv.org/abs/2410.21309

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