Vacuum Chamber of the MEPhIST-1 Tokamak

One of the most important structural elements of a tokamak is a vacuum discharge chamber, which satisfies specific requirements concerning the induction method of plasma generation and, accordingly, the presence of alternating magnetic fields additionally acting on the chamber. Moreover, the chamber should not only be able to create and confine a current plasma but also be able to diagnose its parameters through appropriate pipes. The small spherical tokamak being created at MEPhI for both educational and research purposes has an extensive program of such studies; therefore, the discharge chamber should not only allow fast evacuation and withstand alternating magnetic fields but also be convenient for measuring its parameters, using various diagnostics, as well as allow quick replacement of internal elements and introduction of additional power into the chamber. The paper describes the design of the vacuum chamber of the MEPhIST-1 tokamak, which meets these requirements, and presents calculations to justify the choice of material and the thickness of the characteristic elements of the chamber, and also presents the test results of the finished chamber.