Generation of spherical and cylindrical shock acoustic waves from   optical breakdown in water, stimulated with femtosecond pulse
  Using shadow photography technique we have observed shock acoustic wave from optical breakdown, excited in water by tightly focused Cr:Forsterite femtosecond laser beam, and have found two different regimes of shock wave generation by varying only the energy of laser pulse. At low energies a single spherical shock wave is generated from laser beam waist, and its radius tends to saturation with energy increasing. At higher energies long laser filament in water is fired, that leads to the cylindrical shock wave generation, which longitude increases logarithmically with laser pulse energy. From shadow pictures we estimated maximal velocity in front or shock wave of 2300+/-150m/s and pressure of 1.0+/-0.1 GPa 
F.V.Potemkin, E.I. Mareev, A.A. Podshivalov and V.M.Gordienko
physics.plasm-ph physics.flu-dyn