First observation of high-spin states in $^{214}$Po: Probing the valence space beyond $^{208$}Pb

Excited states in Po-214 have been populated using the O-18 + Pb-208 reaction at 85-MeV beam energy and studied with the Euroball IV gamma-multidetector array. The level scheme has been built up to similar to 2.7-MeV excitation energy and spin I = 12 (h) over bar from the triple-gamma coincidence data. Spin and parity values of most of the observed states have been assigned from the gamma-angular properties. The configurations of the yrast states are discussed using results of empirical shell-model calculations and by analogy with the neighboring nuclei. The Po-214 level scheme established in this work constitutes an important step for the determination of the effective nucleon-nucleon interactions beyond N = 126