Non-adiabatic electron-optical system for 170GHz/1MW/CW gyrotron K.A. Leshcheva, A.L. Goldenberg, M.Y. Glyavin and V.N. Manuilov EPJ Web Conf., 149 (2017) 04035 Published online: 04 August 2017 DOI: 10.1051/epjconf/201714904035