They found that when the equivalent of 50 μmol photons mp−2 s−1 is provided during 1.5 μs pulses of 5000 μmol photons mp−2 s−1 followed by 148.5 μs dark periods, photosynthesis is the same as in continuous 50 μmol photons mp−2 s−1. Data support the theory that photons in pulses of 100 ps or shorter are absorbed and stored in the reaction centers to be used in electron transport during the dark period.