Nanosecond imaging study on laser ablation of liquid benzene

KrF excimer laser ablation of liquid benzene was studied by a nanosecond imaging technique. The ejection of a plume followed by remarkable transient morphological changes took place, which was directly observed over a wide range of the fluence. From imaging data, an ablation threshold was determined to be 100 mJ/cm2 and ablation behavior induced by electronic excitation of liquid molecules is considered. A delay time prior to the plume ejection is about 40±20 ns, while the remarkable morphological change ranges from sub-μs to ms time regime.