Determination of rf electric field strengths in deuterium from satellite structure of Balmer lines

Abstract

In a linear magnetoplasma withn _e≦5×10¹⁸ m⁻³ microwaves with frequencyf=34.8 GHz and powerP≦100 kW were focussed with a quasi-optical horn-lens system. The profiles of the deuterium lines D_β, D_γ, and D_δ were recorded from the focus. The profiles show a satellite structure which is generated by the rf electric field. Beside the first order satellites which can be resolved from the main line, even second order satellites were detectable. Comparing the satellites' intensities with theory it is possible to determine the electric field strength in the focus. Due to a sensitive dependence of the satellites' intensities upon the polarization direction one can also determine an unknown polarization direction.