Ratios of the cross sections for the 10 B( n , α ) 7 Li reaction to the 6 Li( n , t ) 4 He reaction

The ratios of the differential and angle-integrated cross sections for the 10 B( n , α ) 7 Li reaction (including ( n , α ), ( n , α 0 ) and ( n , α 1 )) to the 6 Li( n , t ) 4 He reaction are obtained by re-analyzing our previous measurement data to avoid the uncertainty of the neutron fluences. Present results, with much smaller uncertainties and covering a large neutron energy region from 1.0 eV to several MeV, will be useful in the improvement of the neutron cross section standards. The normalized ratios of the differential and angle-integrated cross sections are in good agreement with the ratios calculated from the evaluation data in the ENDF/B-VIII.0 and JEFF-3.3 libraries. In the neutron energy region from 1.0 to 1.0 keV, the relative uncertainties of the present ratios are significantly reduced compared with those of our previous results of both the 10 B( n , α ) 7 Li and the 6 Li( n , t ) 4 He reactions. New measurements for the 10 B( n , α ) 7 Li reaction with higher precision are demanded, especially in the neutron energy region higher than 0.5 MeV where the relative uncertainties of the present ratios are dominated by those of the previous 10 B( n , α ) 7 Li cross sections which are larger than those of the 6 Li( n , t ) 4 He cross sections.