|
Production of high quality relativistic electron beams driving compact TW laser radiation interaction with plasmaJul. 25, 2006Japan Atomic Energy Agency (The President: Yuichi Tonozuka) has been studying on acceleration of charged particles by high intensity electromagnetic pulses that ultra-short pulse lasers produce. Recently, the scientists at JAEA have conducted experiments, in which the high quality relativistic (20 MeV) electron beam were observed in the interactions between 3TW/70fs Ti:Sapphire laser pulse and plasmas. The work was done by Dr. Michiaki Mori (High-field science group, Quantum Beam Science Directorate, JAEA) and his collabolators, who belong to the High-field science group (The Group leader: Dr. Hiroyuki Daido) and Laser accelerator group (The Group leader: Dr. Sergei V. Bulanov) at Advanced Photon Research Center (Director: Dr. Toyoaki Kimura) in Quantum Beam Science Directorate (Director: Dr. Yoshiaki Kato). The results shows a possibility of high quality femtosecond electron beam generation with compact, relatively low energy, and high repetition rate lasers, which is of the key importance for development of the next generation high energy electron accelerators and for broad range of applications in fundamental science, technology, and medicine. The electron acceleration mechanism in the laser-plasma interaction is based on the original idea of the wake-field generation suggested by Prof. Toshiki Tajima (General director of Kansai Photon Science Institute, JAEA) and Prof. John M. Dawson in 1979. Within this approach, the regular electric field structure is produced in plasma by short laser pulse. The electric field of laser wake has several orders of magnitude higher than that of traditional charged particle accelerators. Therefore, the feature of laser accelerators can reduce its size to smaller than 1/100. In the recent experiments by Dr. Michiaki Mori et al., high controllability of the femtosecond electron beam parameters has been demonstrated. This opens up a way toward development of compact electron accelerators with tunable energy. This experimental results are summarized in the paper published in PHYSICS LETTERS A (Elsevier Science), Vol. 356, Mori et al.: �Transverse dynamics and energy turning of fast electrons generated in sub-relativistic intensity laser pulse interaction with plasmas�, pp146-151, 2006. |
