The consistency of the data for neutron fission averaged cross-sections of threshold reactions: a study on the cross-section of 46Ti(n,p)46Sc, 47Ti(n,p)47Sc, 48Ti(n,p)48Sc and 64Zn(n,p)64Cu reactions.

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.

Averaged cross sections for the reactions (68)Zn(n,p)(68g)Cu and (68)Zn(n,p)(68m)Cu for a (235)U fission neutron spectrum.

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.