Parameters of plasma bunches generated in a long mirror trap under conditions of gyromagnetic autoresonance

Temporal evolution of the spectrum and intensity of bremsstrahlung generated by the plasma bunches formed in a symmetric long mirror trap under conditions of gyromagnetic autoresonance was studied experimentally in detail. Bremsstrahlung was detected by two identical detectors installed in the axial and radial directions with respect to the stationary magnetic field. The results show that the radiation is spatially inhomogeneous. The parameters of the spectra measured in the radial direction strongly depend on the amplitude of the pulsed magnetic field, while the spectra measured in the longitudinal direction are determined mainly by the ECR conditions in the phase of filling the trap with the primary plasma. The integrated intensities, obtained with allowance for the refined form factors of the generated bunches recorded using the high-speed photochronography, made it possible to determine the number of primary plasma particles trapped in the autoresonance mode. © 2019 Published under licence by IOP Publishing Ltd.