EN
The origin and dynamic properties of the green fluorescence of Cs_{2} excited by laser lines in the 457-488 nm range are studied. Emphasis is placed on the analysis of the 501-527 nrn range. The identified fluorescence line progressions are attributed to the E'(3)^{1}П_{u} → X^{1}∑^{+}_{g} transition. An extension of the attractive branch of the E'(3)^{1}П_{u} potential towards longer inter-nuclear distances is reconstructed by the semi-classical method. A narrow feature at 522 nm is found to be connected with a minimum of the difference potentiał. The lifetime values are measured. The multicomponent fluorescence decays are interpreted as evidence of perturbations of the E'(3)^{1}П_{u} state by a number of bound and repulsive states of dicherent symmetry. The predissociation rates are estimated.