Study of the (n,α)reaction on 143Nd and 147Sm with neutron energy high resolution

The results are reported of the experiment on 147Sm(n, a)144Nd and 143Nd(n, a)140Ce reactions with a resolution of 4 ns/m. Total a-widths of 147Sm neutron resonances were measured up to 700 eV and of 143Nd resonances up to 3 keV as well as the cross sections of 147Sm-up to 3 keV. The dependence of mean a-widths vs neutron energy was studied in the energy range up to 3 keV. The experiment pointed out to considerable fluctuations in cross sections if averaged over 100 eV interval (containing 10-15 resonances). At least 3 resonances with a-widths exceeding the mean width by a factor of 5-10 were observed up to 1.8 keV