Plasma wakefield accelerator experiments in KEK

A plasma wakefield experiment is discussed. It uses an existing linac with a relativistic beam, which is separated into several bunches by the RF field. Specifically, use is made of the positron linac, the injector of the Photon Factory (PF), and the TRISTAN Accumulation Ring of the National Laboratory for High Energy Physics (KEK). The preceding bunches generate the wakefield in a plasma to accelerate or decelerate the following bunches. The linear theory predicts an accelerating gradient of approximately 80 MeV/m for this experiment.<>