Plasma wakefield for particles acceleration and Hf-generation

Wakefields, excited in plasma by a short electron bunch or a train of bunches and by laser beat-wave or a short laser pulse, are reviewed as a tool for elaboration of accelerators of new generation and for development of new principles of HF-generators construction. The researching works performed in NSC KIPT and planned in the future are discussed. The state of art and perspectives of theoretical and experimental investigations are considered. The recent achievements in the laboratories of the world are represented