Fluorescence of dyes at supersaturation pump powers

An analysis was made of the hypothesis that the lifetime of excited particles is reduced, by a large factor, in optical fields of supersaturation intensities. This hypothesis had been put forward earlier to account for the unusual increase in the fluorescence intensity of dyes at high pump powers. The profiles of the pump and fluorescence pulses were recorded for an ethanol solution of phenalemine F-510 with the excited-particle lifetime 6.6 ns when the pump intensity was I₀ = 10²³ — 10²⁷ cm^–2 s^–1 at λ = 532 nm. The excited-particle lifetime of 6.6 ns was not affected by high pump intensities.