Summary: We describe the process of nanoparticle formation during pulsed laser ablation in an inert gas atmosphere. We investigated the interaction between laser ablated plumes and shock waves using one-dimensional Eulerian fluid dynamics equations combined with a rate equation relating to a classical nucleation model of supersaturated vapours. We found a certain case wherein the rate of nanoparticle formation becomes higher when a reflected shock wave passes through the plume. In that particular case, the nucleation and nanoparticle growth can be carried out as separate processes.