Velocity spectra from explosively driven powders and balls

The capability to measure velocity distributions using Photon Doppler Velocimetry (PDV) has given rise to much data that were not measurable with previous velocimetry techniques. In our PDV measurements on explosively driven metals, we have often seen a single velocity disappear in a wide distribution of velocities. We have attributed this to HE gases, metal pieces, or a mix emerging from cracks in the metal after it fails. However, we are unaware of any experiments that demonstrate this interpretation. We have applied X-rays, cameras and PDV to explosively driven powders, balls and brass rings and found PDV spectra similar to what we observed in our experiments in which the metal fails. We present these spectra to help workers interpret their velocity spectra.