Bremsstrahlung emission and plasma characterization driven by moderately relativistic laser-plasma interactions

Sushil Singh; Chris D. Armstrong; Ning Kang; Lei Ren; Huiya Liu; Neng Hua; Dean R. Rusby; Ondřej Klimo; Roberto Versaci; Yan Zhang; Mingying Sun; Baoqiang Zhu; Anle Lei; Xiaoping Ouyang; Livia Lancia; Alejandro Laso Garcia; Andreas Wagner; Thomas Cowan; Jianqiang Zhu; Theodor Schlegel; Stefan Weber; Paul McKenna; David Neely; Vladimir Tikhonchuk; Deepak Kumar

doi:10.1088/1361-6587/abcf7e

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arXiv · 2009.12307

Bremsstrahlung emission and plasma characterization driven by moderately relativistic laser-plasma interactions

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Abstract

Relativistic electrons generated by the interaction of petawatt-class short laser pulses with solid targets can be used to generate bright X-rays via bremsstrahlung. The efficiency of laser energy transfer into these electrons depends on multiple parameters including the focused intensity and pre-plasma level. This paper reports experimental results from the interaction of a high intensity petawatt-class glass laser pulses with solid targets at a maximum intensity of $10^{19}$ W/cm$^2$. In-situ measurements of specularly reflected light are used to provide an upper bound of laser absorption and to characterize focused laser intensity, the pre-plasma level and the generation mechanism of second harmonic light. The measured spectrum of electrons and bremsstrahlung radiation provide information about the efficiency of laser energy transfer.

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Sushil Singh, Chris D. Armstrong, Ning Kang, Lei Ren, Huiya Liu, Neng Hua, Dean R. Rusby, Ondřej Klimo, Roberto Versaci, Yan Zhang, Mingying Sun, Baoqiang Zhu, Anle Lei, Xiaoping Ouyang, Livia Lancia, Alejandro Laso Garcia, Andreas Wagner, Thomas Cowan, Jianqiang Zhu, Theodor Schlegel, Stefan Weber, Paul McKenna, David Neely, Vladimir Tikhonchuk, Deepak Kumar. 2020-09-25. Bremsstrahlung emission and plasma characterization driven by moderately relativistic laser-plasma interactions. https://doi.org/10.1088/1361-6587/abcf7e

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