S.V. Kuzikov – Head of Laboratory, Institute of Applied Physics of RAS (N. Novgorod) E-mail: kuzikov@appl.sci-nnov.ru

Yu.V. Rodin – Leading Engineer, Institute of Applied Physics of RAS (N. Novgorod)

E-mail: wish26@yandex.ru

A.A. Vikharev – Research Scientist, Institute of Applied Physics of RAS (N. Novgorod) E-mail: alvikharev@appl.sci-nnov.ru

We develop two concepts of vacuum RF loads based on a cavity surrounded by absorbing water vessel with dielectric walls to be transparent for microwaves. We propose to use either corrugated walls of the metallic cavity or corrugated dielectric walls of the water vessel itself. These corrugations allow essentially reducing peak surface RF fields. Water cooling also provides good opportunities to operate the loads at high average RF power. The proposed loads have being simulated to satisfy the parameters: 50 MW peak/25 kW average.

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