On the ''threshold'' energy of the Frenkel-defect formation by fast particles

Calculated was the cross-section σ(E) of the Frenkel defect formation as a result of the elastic scattering of fast particle of energy E from a crystal atom with provision for true dependence of the probability W(T) of defect formation on the value of transmitted energy T, which considerably differs from the step probability. σ(E) obtained by such a method goes to zero at some value of E, designated as Esub(d). However, the cross section of defect formation at high energies does not turn to associate with the found Esub(d) by the known ratio σ(E) approximately (Tsub(max)/Esub(d)-1) ratio; the similar association widety used in titerature is erroneous, because it results from incorrect step representation of the probability W(T). σ(E) value obtained qualitatively coincides with experimental dependences for Si and Ge, and a good coincidence of theoretical and experimental curves is achieved by selection of numerical values of characteristic theory parameters