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Doppler Effects

Ion beams are accelerated to high voltages (speeds $\approx 10^{5}$ ms-1) in laser photofragment experiments in order to utilise kinematic compression. This reduces the Doppler broadening of spectral lines, giving high resolution spectra (<0.01 cm-1  resolution) when used in conjunction with low linewidth laser radiation. The high speed of the molecular ion beam (which travels in the same direction as the laser radiation) causes a Doppler shift.





Tim Gibbon
1999-09-06