β-decay feeding intensity distributions for 103,104mNb

The β decays of 103,104mNb were studied with the Summing NaI(Tl) (SuN) detector at the National Superconducting Cyclotron Laboratory. The β-decay feeding intensity distribution Iβ(E) for each isotope was extracted by measuring γ rays in coincidence with an emitted electron. The Iβ(E) was extracted via the total absorption spectroscopy technique. The Iβ(E) for each nucleus was compared to predictions made by the quasiparticle random-phase approximation (QRPA) model which is commonly used to calculate β-decay properties for astrophysical applications. The main goal was to provide experimental data for neutron-rich nuclei, relevant to the astrophysical r process. In addition, the extracted β-decay feeding intensity distributions can lead to a better understanding of nuclear structure in a region of rapid structure changes around A = 100. Finally, experimental data for 104mNb are also of interest to antineutrino studies of nuclear reactors