Benchmarking the extraction of statistical neutron capture cross sections on short-lived nuclei for applications using the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>β</mml:mi></mml:math>-Oslo method

Abstract

Numerous scientific fields including astrophysics, nuclear power, and nuclear forensics require a knowledge of basic nuclear properties for large numbers of short-lived, radioactive isotopes far removed from stable nuclei. Neutron-capture cross sections are one such piece of nuclear data where direct measurements are not possible and theoretical predictions can vary by orders of magnitude. A recently developed indirect technique for inferring neutron capture rates, the $\ensuremath{\beta}$-Oslo method, has been introduced but not compared against a known, directly measured neutron capture cross section. To provide this benchmark, two indirect methods based on $\ensuremath{\beta}$ decay and charged-particle reactions were used to extract the nuclear level density and $\ensuremath{\gamma}$-ray strength function of $^{51}\mathrm{Ti}$. The nuclear level density and $\ensuremath{\gamma}$-ray strength function from the two data sets were found to be equivalent and were used to extract the neutron capture cross section of $^{50}\mathrm{Ti}$ which agrees with previous direct measurements at high neutron energies. The results demonstrate the validity of the $\ensuremath{\beta}$-Oslo method for extracting neutron capture cross sections of short-lived nuclei and provide a sufficiently small uncertainty to be used in various applications.