The high-frequency stark effect in the balmer lineD-alpha

The calculation of the emission lineD _α under the influence of a linearly polarizedrf-field (the oscillation frequency is equal to 34.8 GHz, the electric field amplitude is of the order 200 kV/m) delivers satellites on both sides of the main peak. Deviations from symmetry with respect to the average wavelength of the central line originate from the fine structure: the entire satellite structure is slightly shifted (～ 1 pm) to the red and the intensity of the blue satellite is about 15% higher than that of the red one. The numerical analysis has incorporated also the Zeeman effect by a static magnetic field (140 mT) parallel to therf-electric field as well as Doppler broadening on account of the temperature of the deuterium atoms which amounts to 1000 K. The comparison of measured and calculated line shapes allows to determine therf-electric field strength with an accuracy of about 5%.