A re-examination of the 19F(n,γ)20F reaction

Abstract

A re-examination of the 19F(n,γ)20F reaction has been conducted in which several factors were selected for optimization. These included sample purity, high statistical precision and hence sensitivity, sufficient energy precision and resolution to permit confident application of the Ritz combinational method, and efficiency calibration to test intensity balance in a meaningful way. The results obtained, besides increasing level-energy precision, revealed the likely existence of a new level and failed to agree with some aspects of earlier studies. The degree with which direct capture plays a role in this reaction was also explored and found to account for 35–50% of the 9 mb capture cross section. The neutron separation energy was found to be 6601.36 ± 0.05 keV, based upon the mass scale. A new level, forming a doublet with that at 3587 keV, was inferred to be at 3590 keV.