By using molecular dynamics methods, it was shown that the initial momentum anisotropy of 3keV primary knock-on atoms was modulated into near-isotropy during the collisional phase of displacement cascades. In the case of 100MeV primary knock-on atoms, where electron bursts were produced by energetic recoil atoms, a new mechanism was proposed for defect production by such electron bursts.

Y.Taji: Radiation Effects and Defects in Solids, 1994, 129[1-2], 69-75