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arXiv · 2011.09979

Measurements of the growth and saturation of electron Weibel instability in optical-field ionized plasmas

Chaojie Zhang·Jianfei Hua·Yipeng Wu·Yu Fang·Yue Ma·Tianliang Zhang·Shuang Liu·Bo Peng·Yunxiao He·Chen-Kang Huang·Ken A. Marsh·Warren B. Mori·Wei Lu·Chan Joshi
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Abstract

The temporal evolution of the magnetic field associated with electron thermal Weibel instability in optical-field ionized plasmas is measured using ultrashort (1.8 ps), relativistic (45 MeV) electron bunches from a linear accelerator. The self-generated magnetic fields are found to self-organize into a quasi-static structure consistent with a helicoid topology within a few ps and such a structure lasts for tens of ps in underdense plasmas. The measured growth rate agrees well with that predicted by the kinetic theory of plasmas taking into account collisions. Magnetic trapping is identified as the dominant saturation mechanism.

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Chaojie Zhang, Jianfei Hua, Yipeng Wu, Yu Fang, Yue Ma, Tianliang Zhang, Shuang Liu, Bo Peng, Yunxiao He, Chen-Kang Huang, Ken A. Marsh, Warren B. Mori, Wei Lu, Chan Joshi. 2020-11-19. Measurements of the growth and saturation of electron Weibel instability in optical-field ionized plasmas. https://doi.org/10.1103/physrevlett.125.255001

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