Copper coil magnetic system study in a 60 GHz gyrotron design

Abstract

This paper presents the study of a gyrotron magnetic system with a field intensity of 2.45 T and a triode magnetron injection gun system to achieve electron trajectories into the cavity operating zone to generate a 60 GHz radiofrequency used in electron cyclotron resonance heating applications. The operating mode of the gyrotron is TE4,3. A copper coil system arrangement of four solenoids with a stationary current of 750 A and a magnetic compression of 16.53 with a magnetic field homogeneity of 0.10% over a length of 56 mm in the operating zone was designed. A very good approximation of the magnetic field profile of the copper coil system was obtained using a novel formulation derived from the geometry of the coils. The magnetron injection gun parameters were obtained applying the trade-off equations, resulting in a cathode radius of 13.5 mm. The helicoidal and laminar trajectories of the electrons with a transverse-velocity of 1.175 are obtained from the magnetic and gun systems. The resulting trajectories are generated using the 2-D EGUN code. The study represents an effort to create an Experimental Theoretical Fusion Platform of the High Magnetic Field Program at the Autonomous University of Nuevo León (UANL).