The Laser proton acceleration in the strong charge separation regime

Nishiuchi, Mamiko; Fukumi, Atsushi*; Daido, Hiroyuki; Li, Z.*; Sagisaka, Akito; Ogura, Koichi; Orimo, Satoshi; Kado, Masataka; Hayashi, Yukio; Mori, Michiaki; Bulanov, S. V.; Esirkepov, T. Z.; Nemoto, Koichi*; Oishi, Yuji*; Nayuki, Takuya*; Fujii, Takashi*; Noda, Akira*; Iwashita, Yoshihisa*; Shirai, Toshiyuki*; Nakamura, Shu

We report the experimental results of proton acceleration as well as the simple one-dimensional model which explain our experimental data. The proton acceleration experiment was carried our with the TW short pulse laser irradiated on the Tantalum thin-foil target (3m thickness) with the intensity of 310 Wcm. Accelerated protons exhibit the typical energy spectrum with the two component-quasi-Maxwellian parts with the high energy cut-off. We could successfully explain the higher energy part as well as the cut off energy of the proton spectrum, with the simple-one-dimensional model based on the strong charge separation regime, which is the extension of the model proposed by Passoni et al. [Phys. Rev. E, 69 (2004) 026411].