RESUMO
The consistency of the published values for fission averaged cross-sections of threshold reactions induced in a nuclear reactor is analyzed. The influence of the literature data involved in the determination of these cross-sections is discussed. Renormalizations based on cross-sections value for the standard reactions, isotopic abundances of the precursors and radiation emission probabilities of the radionuclide under study and the monitor, are applied to the evaluation of the cross-sections for the reactions: (46)Ti(n,p)(46)Sc; (47)Ti(n,p)(47)Sc; (48)Ti(n,p)(48)Sc; and (64)Zn(n,p)(64)Cu.
Assuntos
Radioisótopos de Cobre/química , Nêutrons , Fissão Nuclear , Radiometria/métodos , Escândio/química , Titânio/química , Radioisótopos de Zinco/química , Radioisótopos de Cobre/efeitos da radiação , Isótopos/química , Isótopos/efeitos da radiação , Doses de Radiação , Escândio/efeitos da radiação , Titânio/efeitos da radiação , Radioisótopos de Zinco/efeitos da radiaçãoRESUMO
Making use of the method developed in our laboratory for the simultaneous determination of cross sections leading to both the ground and metastable states, we have measured the (68)Zn(n,p)(68g)Cu and (68)Zn(n,p)(68m)Cu reactions, using Zn enriched to 99.4% in its isotope (68)Zn. The measured cross sections are (15.04+/-0.35) and (3.69+/-0.30)microb for the ground and metastable state, respectively. However, a direct determination of the cross section leading to the metastable state gives a value of (4.75+/-0.38)microb. A possible reason for this discrepancy-which is outside experimental uncertainties-is that some tabulated values used in our calculations for the decay parameters of (68g)Cu and (68m)Cu, have either larger than quoted, or unknown systematic, uncertainties.