EXPERIMENTS OF HIGH-ENERGY GAIN LASER WAKEFIELD ACCELERATION

The wakefield acceleration of electrons has a great potential for the future accelerator because of its high accelerating field gradient. We have obtained over 100 MeV acceleration gain by the wakefield generat ed by a 2 TW Ti:sapphire laser system. In the acceleration experiment, the 17 MeV electrons from a linac were used for the injection beam. T he synchronization between the RF signal and the laser pulse was achie ved within the time jitter of 3.7 ps. Due to the self-focusing and ion ization, a long propagation length and high field gradient were realiz ed. The self-focusing effect of the laser was confirmed by the laser s potsize measurement along the beam axis. The plasma density oscillatio n was measured by using the frequency domain interferometry. The accel eration gain expected from the plasma density measurement was consiste nt with the result of the acceleration experiments. (C) 1998 Elsevier Science B.V. All rights reserved.