The new concepts in designing the CW high-current linacs

The concepts in designing of the two types of high-current proton (deuteron) linacs having the electronuclear purpose with the output energy about 1 GeV and currents 200-300 mA (the first type) and 10 mA (the second type) are developed. The major problems arising in both cases is ensuring high reliability and efficiency of linacs. For the first type the high reliability is mainly connected with solving of the problem of minimizing the particles losses down to the level of 10^-5 and of building the reliable superhigh-power RF power supply system. For the second type the problem of increasing the efficiency is of major importance. In the report the ways to solving of these problems by means of using the superconducting solenoidal focusing together with the optimized RF power supply systems (for the first linac type) and the superconducting accelerating cavities (for the second type) are shown