179Ta(n, γ) cross-section measurement and the astrophysical origin of the 180Ta isotope

^180mTa is nature's rarest (quasi) stable isotope and its astrophysical origin is an open question. A possible production site of this isotope is the slow neutron capture process in asymptotic giant branch stars, where it can be produced via neutron capture reactions on unstable ¹⁷⁹Ta . We report a new measurement of the ¹⁷⁹Ta ( n , γ ) ¹⁸⁰Ta cross section at thermal-neutron energies via the activation technique. Our results for the thermal and resonance-integral cross sections are 952 ± 57 and 2013 ± 148 b, respectively. The thermal cross section is in good agreement with the only previous measurement [Phys. Rev. C 60, 025802 (1999)], while the resonance integral is different by a factor of ≈ 1.7 . While neutron energies in this work are smaller than the energies in a stellar environment, our results may lead to improvements in theoretical predictions of the stellar cross section.