Experimental and numerical investigation of auroral cyclotron maser processes

In this paper the results of PiC code simulations and a laboratory experiment to investigate the evolution of an electron beam subject to magnetic compression of up to a factor of 30 is outlined. The experiment consisted of a 75 keV electron beam with significant initial sbeam with significant initial spread in velocity injected into an adjustable convergent magnetic field generated by a solenoid arrangement. The aim was to produce a horseshoe shaped electron velocity distribution and study the subsequent evolution of this distribution within an interaction waveguide at the peak of the axial magnetic field.