Fragmentation of Colliding Discs
  We study the phenomena associated with the low-velocity impact of two solid discs of equal size using a cell model of brittle solids. The fragment ejection exhibits a jet-like structure the direction of which depends on the impact parameter. We obtain the velocity and the mass distribution of the debris. Varying the radius and the initial velocity of the colliding particles, the velocity components of the fragments show anomalous scaling. The mass distribution follows a power law in the region of intermediate masses. 
F. Kun, H. J. Herrmann (PMMH, Espci, Paris)