The Mossbauer effect has been used t o study radiation damage in a-iron, doped with 0.6 at?: 0 s and 4 atyo Pt. The samples were irradiated in a nuclear reactor at 4.6 K. The Mossbauer nuclei of Irlg3 and Ada7 were produced by capture of thermal neutrons in OslS2 or Pt196, a process which simultaneously could lead t o radiation damage. Compared with annealed samples, the average magnetic field was reduced after the irradiation by about 2% and the line width was increased by approximately 30%. Isochronal annealing processes were studied. The annealing of the irradiation effects took place primarily between 90 and 140 K with activation energies in the range between 0.30 and 0.40 eV. These effects are interpreted as mainly due to a vacancy as nearest or next nearest neighbour of the displaced Mossbauer atom combined with an interstitial several lattice sites away from the vacancy. The Mossbauer atom does not come to rest as an interstitial atom. These results are in good agreement with results from computer experiments of Vineyard's group.
Mit dem MoBbauereffekt wurde die Strahlenschadigung in a-