Figure 2: Time-resolved PM transients.

PM signal under (a) continuous and (b) pulsed laser excitation at 532 nm. The transients show the intensity variation of the centre of a continuous probe beam laser reflected off of the water surface measured at the PMT positioned in the far field. Open symbols are experimental data and continuous lines represent the numerical calculations using S(t)/S(0), in which S(0) is the signal at t=0. The error bars for the experimental data are smaller than 0.2%.