Proceedings Article | 14 May 2019
KEYWORDS: Light sources, Plasma, Aluminum, Electron beams, Femtosecond phenomena, Laser systems engineering, Ionization, Optical simulations, Plasma generation, Laser ablation
A compact light source can be utilized by using an electron beam from a Laser wakefield accelerator, of which merits are smaller size, lower radiation hazard with local shielding, and lower cost compared to conventional RF accelerators. To use as an injector for an accelerator, such as, storage rings or linacs, the high vacuum environment is important for longer lifetime in a cycle accelerator and higher repetition operation. The use of metallic target was suggested [1] and demonstrated using 30 TW fs laser system at KAERI [2,3]. The results showed not only the possibility of high-vacuum, high-repetition operations, but also high stability in beam energy and beam pointing. Due to the optical ionization process up to Al+11 by main laser of the pre-plasma, which is laser ablated plasma typically ionized Al+3 ~ Al+5 by ns laser, the mechanism of laser electron acceleration is different to fully ionized gas target like He gas. The simulation result shows the difference between the fully ionized plasma and partially ionized plasma. We present the experimental and simulation results and discuss the issues on target materials and the possibility of multistage operation.
[1] Ya. V. Getmanov, O. A. Shevchenko, N. A. Vinokurov, "Electron injection into a cyclic accelerator using laser wakefield acceleration," Proceedings of IPAC’10, Kyoto, Japan, 1503-1505 (2010).
[2] Jaehoon Kim, Younghun Hwangbo, Woo-Je Ryu, Kyung Nam Kim, and Seong Hee Park, “Density profile of a line plasma generated by laser ablation for laser wakefield acceleration,” Journal of Instrumentation 11, C03012 (2016).
[3] Seong Hee Park et. al, to be submitted.
