title: ATOMIC DISPLACEMENTS INDUCED BY HIGH DENSITY ELECTRONIC EXCITATION IN IRON authors: A. Iwase*, Y. Chimi*, N. Ishikawa* and T. Kambara# affiliations: *Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun , Ibaraki, 319-1195, Japan #The Institute of Physical and Chemical Research (RIKEN), W ako-shi, Saitama, 351-0198, Japan summary: We have observed that atomic displacements (defect production and annihil ation) are induced by high density electronic excitation in pure iron irradi ated with ~100 MeV and GeV heavy ions. The cross sections for defect product ion and annihilation are non-linearly correlated with electronic stopping po wer, Se. They also depend on the ion-velocity.