Generation of stable and low-divergence 10-MeV quasimonoenergetic electron bunch using argon gas jet

Mori, Michiaki; Kondo, Kiminori; Mizuta, Yoshio*; Kando, Masaki; Kotaki, Hideyuki; Nishiuchi, Mamiko; Kado, Masataka; Pirozhkov, A. S.; Ogura, Koichi; Sugiyama, Hironori*; Bulanov, S. V.; Tanaka, Kazuo*; Nishimura, Hiroaki*; Daido, Hiroyuki

The pointing stability and divergence of a quasimonoenergetic electron bunch generated in a self-injected laser-plasma acceleration regime using 4 TW laser is studied. A pointing stability of 2.4 mrad root-mean-square (RMS) and a beam divergence of 10.6 mrad (RMS) were obtained using an argon gas-jet target for 50 sequential shots, while these values were degraded by a factor of three at the optimum condition using helium. The peak electron energies were 8.50.7 MeV and 24.83.6 MeV using argon and helium, respectively. The experimental results indicate that the different propagation condition could be generated with the different material, although it is performed with the same irradiation condition.