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arXiv · 2003.07053

Generation of highly-polarized high-energy brilliant $\gamma$-rays via laser-plasma interaction

Kun Xue·Zhen-Ke Dou·Feng Wan·Tong-Pu Yu·Wei-Min Wang·Jie-Ru Ren·Qian Zhao·Yong-Tao Zhao·Zhong-Feng Xu·Jian-Xing Li
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Abstract

Generation of highly-polarized high-energy brilliant $\gamma$-rays via laser-plasma interaction has been investigated in the quantum radiation-reaction regime. We employ a quantum-electrodynamics particle-in-cell code to describe spin-resolved electron dynamics semiclassically and photon emission and polarization quantum mechanically in the local constant field approximation. As an ultrastrong linearly-polarized (LP) laser pulse irradiates on a near-critical-density (NCD) plasma followed by an ultrathin planar aluminum target, the electrons in NCD plasma are first accelerated by the driving laser to ultrarelativistic energies, and then head-on collide with reflected laser pulse by the aluminum target, emitting brilliant LP $\gamma$-rays due to nonlinear Compton scattering with an average polarization of about 70\% and energy up to hundreds of MeV. By comparison, as a conical gold target filled with NCD plasma is employed, the linear polarization degree, collimation and brilliance of emitted $\gamma$-ray beam are all significantly improved due to the enhanced strong laser-driven quasi-static magnetic field in plasmas. Such $\gamma$-rays can be produced with currently achievable laser facilities and find various applications in high-energy physics and astrophysics.

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Kun Xue, Zhen-Ke Dou, Feng Wan, Tong-Pu Yu, Wei-Min Wang, Jie-Ru Ren, Qian Zhao, Yong-Tao Zhao, Zhong-Feng Xu, Jian-Xing Li. 2020-03-16. Generation of highly-polarized high-energy brilliant $\gamma$-rays via laser-plasma interaction. https://arxiv.org/abs/2003.07053

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