Developments in laser wakefield accelerators: From single-stage to two-stage*
Li Wen-Tao, Wang Wen-Tao†, Liu Jian-Sheng‡, Wang Cheng, Zhang Zhi-Jun, Qi Rong, Yu Chang-Hai, Li Ru-Xin, Xu Zhi-Zhan
Fig. 12. Single-shot electron beam spectra from the two-stage LWFA with the 5-mm-thick second stage. [ 70 ] The plasma densities for the two-segment gas flows were 9 #cod#x00D7; 10 18 cm #cod#x2013;3 and a#cod#x2013;c 2.8 #cod#x00D7; 10 18 cm #cod#x2013;3 , b#cod#x2013;d 3.0 #cod#x00D7; 10 18 cm #cod#x2013;3 , respectively.