Laser-driven proton generation from a thin-foil target with a high-intensity laser

Sagisaka, Akito; Nishiuchi, Mamiko; Pirozhkov, A. S.; Ogura, Koichi; Sakaki, Hironao; Maeda, Shota; Pikuz, T.; Faenov, A. Ya.*; Fukuda, Yuji; Yogo, Akifumi; Kanasaki, Masato; Matsukawa, Kenya*; Mori, Michiaki; Kando, Masaki; Kiriyama, Hiromitsu; Okada, Hajime; Kanazawa, Shuhei; Kondo, Shuji; Shimomura, Takuya; Nakai, Yoshiki*; Tanoue, Manabu; Sakai, Seiji; Watanabe, Yukinobu*; Yamauchi, Tomoya*; Esirkepov, T. Z.; Bulanov, S. V.; Kondo, Kiminori

High-intensity laser and thin-foil interactions produce high-energy particles, hard X-ray, high-order harmonics, and terahertz radiation. A proton beam driven by a high-intensity laser has received attention as a compact ion source for medical and other applications. We have performed several high intensity laser-matter interaction experiments using a thin-foil target irradiated by Ti:sapphire laser (J-KAREN) at JAEA. The pulse duration was typically 40 fs (FWHM). The electron density profiles of the preformed plasma were observed with the interferometer. The high temporal contrast laser system could reduce the preformed plasma. The maximum proton energy gradually increased as the laser performance improved and finally protons of 40 MeV energy were observed at the peak laser intensity of 1 10 W/cm.