Bremsstrahlung emission and plasma characterization driven by moderately relativistic laser-plasma interactions
S. K. Singh, C. Armstrong, Ning Kang, Lei Ren, Huiya Liu, Neng Hua, D. Rusby, O. Klimo, R. Versaci, Yan Zhang, Mingying Sun, Baoqiang Zhu, Anle Lei, Xiaoping Ouyang, L. Lancia, Alejandro Laso García, A. Wagner, T. E. Cowan, Jianqiang Zhu, Theodor Schlegel, S. Weber, P. McKenna, D. Neely, V. T. Tikhonchuk, Deepak Kumar
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.