Anomalous absorption and luminescence of molecular iodine vapors under laser excitation

The dynamics of absorption and the fluorescence of molecular iodine vapors excited by intense laser radiation at lambda = 530 nm are studied. It is shown that the bleaching regime and the dependence of the fluorescence energy on the excitation energy density are substantially different from the calculated data following from the classical concepts. The anomalies observed in the experiments are associated with the light-induced luminescence caused by collective interactions of the molecular ensemble with the resonant excitation field.