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The experiments quantitatively resolved lattice expansion occurring over tens of picoseconds after excitation with a high-power infrared laser. They also demonstrated the subpicosecond creation of a disordered region near the surface. Dynamic processes in condensed matter occur on a time scale dictated by the period of a lattice vibration, typically about 100 femtoseconds. For example, the ALS emits pulses 30 picoseconds in length, which is 300 times too long to resolve events lasting 100 femtoseconds. The Berkeley group used the BTF source to measure x-ray diffraction from an indium antimonide crystal every few picoseconds both before and after laser irradiation at intensities below the threshold for damage.