Collimated Hard X-Rays from Hybrid Laser and Plasma Wakefield Accelerators

Hong Zhang; Jianmeng Wei; Mengyuan Chu; Jiale Zheng; Zhiheng Lou; Ruoxuan Ma; Xizhuan Chen; Hao Wang; Gaojie Zeng; Hang Guo; Yinlong Zheng; Hai Jiang; Yanjie Ge; Kangnan Jiang; Runshu Hu; Jiayi Qian; Jiacheng Zhu; Zongxin Zhang; Yi Xu; Yuxin Leng; Song Li; Ke Feng; Wentao Wang; Ruxin Li

arXiv · 2506.06833

Collimated Hard X-Rays from Hybrid Laser and Plasma Wakefield Accelerators

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Abstract

We report a synergistic enhancement of betatron radiation based on the hybrid laser and plasma wakefield acceleration scheme. Quasi-phase-stable acceleration in an up-ramp plasma density first generates GeV-energy electron beams that act as a drive beam for PWFA, which then further accelerates the witness beam to GeV energies, enhancing both photon energy and flux. A full width at half maximum divergence $(6.1 \pm 1.9)\times(5.8\pm 1.6) $ mrad$^2$ of betatron radiation, a critical energy of $71 \pm 8$ keV, and an average flux of more than $10^{14}$ photons per steradian above 5 keV were all experimentally obtained thanks to this scheme, which was an order of magnitude higher than the previous reports. Quasi-three-dimensional particle-in-cell simulations were used to model the acceleration and radiation of the electrons in our experimental conditions, establishing a new paradigm for compact collimated hard X-ray sources.

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Hong Zhang, Jianmeng Wei, Mengyuan Chu, Jiale Zheng, Zhiheng Lou, Ruoxuan Ma, Xizhuan Chen, Hao Wang, Gaojie Zeng, Hang Guo, Yinlong Zheng, Hai Jiang, Yanjie Ge, Kangnan Jiang, Runshu Hu, Jiayi Qian, Jiacheng Zhu, Zongxin Zhang, Yi Xu, Yuxin Leng, Song Li, Ke Feng, Wentao Wang, Ruxin Li. 2025-06-07. Collimated Hard X-Rays from Hybrid Laser and Plasma Wakefield Accelerators. https://arxiv.org/abs/2506.06833

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