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arXiv · 1907.08877

Polarized ultrashort brilliant multi-GeV $γ$-rays via single-shot laser-electron interaction

Yan-Fei Li·Rashid Shaisultanov·Yue-Yue Chen·Feng Wan·Karen Z. Hatsagortsyan·Christoph H. Keitel·Jian-Xing Li
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Abstract

Generation of circularly-polarized (CP) and linearly-polarized (LP) $γ$-rays via the single-shot interaction of an ultraintense laser pulse with a spin-polarized counterpropagating ultrarelativistic electron beam has been investigated in nonlinear Compton scattering in the quantum radiation-dominated regime. For the process simulation a Monte Carlo method is developed which employs the electron-spin-resolved probabilities for polarized photon emissions. We show efficient ways for the transfer of the electron polarization to the high-energy photon polarization. In particular, multi-GeV CP (LP) $γ$-rays with polarization of up to about 95\% can be generated by a longitudinally (transversely) spin-polarized electron beam, with a photon flux at a single shot meeting the requirements of recent proposals for the vacuum birefringence measurement in ultrastrong laser fields. Such high-energy, high-brilliance, high-polarization $γ$-rays are also beneficial for other applications in high-energy physics, nuclear physics, and laboratory astrophysics.

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Yan-Fei Li, Rashid Shaisultanov, Yue-Yue Chen, Feng Wan, Karen Z. Hatsagortsyan, Christoph H. Keitel, Jian-Xing Li. 2019-11-27. Polarized ultrashort brilliant multi-GeV $γ$-rays via single-shot laser-electron interaction. https://doi.org/10.1103/physrevlett.124.014801

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