Photon correlation in resonance scattering-a new approach to the investigation of the excited states of atoms and molecules

Abstract
It is shown that analysis of the spectral time correlations of resonantly scattered photons is a new Doppler-free method for the investigating excited states of atoms and molecules. By using this method for investigation of the photon correlation, the times of transitions between excited states can be measured. Unlike the usual method of the delayed fluorescence the measurement can be accomplished with a continuous excitation of upper levels.