Laser Guiding at Relativistic Intensities and Wakefield Particle Acceleration in Plasma Channels.

Geddes, C. G. R. ; Toth, C. ; Van Tilborg, J. ; Esarey, E. ; Schroeder, C. B. ; Bruhwiler, D. ; Carey, J. ; Leemans, W. P.

Technical Information Center Oak Ridge Tennessee

关键词: Wakefield accelerators;    Electron beams;    Plasma waves;    Electrons;    Lasers;   

RP-ID  :  DE2005836675

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Electron beams with hundreds of picoCoulombs of charge in percent energy spread at above 80 MeV, and with few milliradian divergence, have been produced for the first time in a high gradient laser wakefield accelerator by guiding the drive laser pulse. Channels formed by hydrodynamic shock were used to guide acceleration relevant laser intensities of at least 1E18W/cm(sup 2) at the guide output over more than 10 Rayleigh lengths at LBNL's l'OASIS facility (10TW, 2E19W/cm(sup 2)). The pondermotive force of the laser pulse drove an intense plasma wave, producing acceleration gradients on the order of 100 GV/m. Electrons were trapped from the background plasma and accelerated. By extending the acceleration length using the guiding channel, the energy of the electron beam was greatly increased, and bunches of small energy spread and low emittance were formed. Experiments varying gas jet length as well assimilations indicate that the high quality beams were formed when beam loading turned off injection after an initial load, producing an isolated bunch, and when that bunch was subsequently accelerated to the dephasing length at which point it rotated in phase space to produce low energy spread.