Adiabatic plasma buncher

In this paper, we present a new scheme of injection into a plasma accelerat or, aimed at producing a high-quality beam while relaxing the demands on th e bunch length of the injected beam. The beam dynamics in the injector, con sisting of a high-voltage pulsed photodiode, is analyzed and optimized to p roduce a lambda (p)/20 long electron bunch at 2.5 MeV, This bunch is inject ed into a plasma wave in which it compresses down to lambda (p)/100, while accelerating up to 250 MeV. This simultaneous bunching and acceleration of a high-quality beam requires a proper combination of injection energy and i njection phase, Preliminary results from simulations are shown to assess th e potentials of the scheme.