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arXiv · 2011.00156

Trapping and acceleration of spin-polarized positrons from $\gamma$ photon splitting in wakefields

Wei-Yuan Liu·Kun Xue·Feng Wan·Min Chen·Jian-Xing Li·Feng Liu·Su-Ming Weng·Zheng-Ming Sheng·Jie Zhang
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Abstract

Energetic spin-polarized positrons are extremely demanded for forefront researches, such as $e^- e^+$ collider physics, but making compact positron sources is still very challenging. Here we put forward an efficient scheme of trapping and acceleration of polarized positrons in plasma wakefields. Seed electrons colliding with a bichromatic laser create polarized $\gamma$ photons which then split into $e^- e^+$ pairs via nonlinear Breit-Wheeler process with an average (partial) positron polarization above 30\% (70\%). Over 70\% positrons are trapped and accelerated in recovered wakefields driven by a hollow electron beam, obtaining an energy gain of 3.5 GeV/cm with slight depolarization. This scheme provides a potential for constructing compact and economical positron sources for future applications.

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Wei-Yuan Liu, Kun Xue, Feng Wan, Min Chen, Jian-Xing Li, Feng Liu, Su-Ming Weng, Zheng-Ming Sheng, Jie Zhang. 2020-10-31. Trapping and acceleration of spin-polarized positrons from $\gamma$ photon splitting in wakefields. https://arxiv.org/abs/2011.00156

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