Investigation of the low-lying levels of 179Hf with the (n, γ) and (n,e) reactions

The excited levels of ¹⁷⁹Hf are investigated using the thermal neutron capture γ-ray and conversion electron spectra measured with the bent crystal diffraction spectrometer in Risø and the β-spectrograph in Riga. The level scheme contains the odd parity rotational bands $\text{7}\text{2}{}^{\mathrm{?}}\text{[514],}\text{1}\text{2}{}^{\mathrm{?}}\text{[510],}\text{5}\text{2}{}^{\mathrm{?}}\text{[512],}\text{1}\text{2}{}^{\mathrm{?}}\text{[521],}\text{3}\text{2}{}^{\mathrm{?}}\text{[512]}$ and $\text{7}\text{2}{}^{\mathrm{?}}\text{[503]}$. The energies of these levels and the intensity ratios of the transitions between them are calculated taking into account the rotation-particle coupling (RPC). The following even parity levels are proposed: 859.0 and 942.2 keV $\text{(}\text{7}\text{2}{}^{\mathrm{+}}\text{and}\text{9}\text{2}{}^{\mathrm{+}}\text{of the}\text{7}\text{2}{}^{\mathrm{+}}\text{[633]}\text{band}\text{)}$; 1004.1 and 1079.2 keV $\text{(}\text{5}\text{2}{}^{\mathrm{+}}\text{and}\text{7}\text{2}{}^{\mathrm{+}}\text{of the}\text{9}\text{2}{}^{\mathrm{+}}\text{[624] + Q(22)}\text{band}\text{)}$; 1186.0, 1199.2 and 1296.4 keV $\text{(}\text{1}\text{2}{}^{\mathrm{+}}\text{,}\text{5}\text{2}{}^{\mathrm{+}}\text{and}\text{3}\text{2}{}^{\mathrm{+}}\text{of the}\text{1}\text{2}{}^{\mathrm{+}}\text{[651]}\text{band}\text{)}$. The levels at 1249.8, 1269.7, 1432.9, 1482.2 and 1755.5 keV, supported by the analysis of the γγ coincidence spectrum and Ge(Li) singles data, are discussed.