nnp FY2013 Annual Report 3.2 Figure 2

Figure 2: a) Radially averaged radial velocity (red color being high velocity and blue being low) as a function of time (y-axis) and radial distance from the petri dish center (x-axis) shows a fast propagating disturbance (white line between R/R0 = 0 and R/R0 = 1) between 0 and 10 milliseconds. It is followed by a slower compaction front seen by the color coded field at later times. b) Radial position (distance from center of petri dish) of the stage 1 disturbance front versus time shows a linear relationship. The slope of this plot provides the velocity of the disturbance front, measured to be 1.7 m/s, thus placing it comparable to an acoustic shock wave (or Rayleigh wave) for this tenuous solid.