The enriched ¹⁶⁴Dy and natural dysprosium targets were activated with the bremsstrahlung beam at end- point energies 7.17, 8.11, 9,75, 12.12, 13.75, 16.6, 18.34, 20.36, and 22.82 MeV. The decay γ-spectra measured with HPGe detector up to 2.4 MeV energy were used to determine yields of the photoactivation reaction ¹⁶⁴Dy(γ,p) ¹⁶³Tb. The γ-spectra following the ¹⁶⁴Dy photoactivation reaction with 20.36 MeV photons allowed to develop the level scheme of ¹⁶³Dy including 37 levels up to 1.44 MeV excitation energy. A number of ¹⁶³Dy levels and γ-lines were observed in the β- decay of ¹⁶³Tb for the first time. The proposed level scheme of ¹⁶³Dy was compared with the results of quasiparticle-plus- rotor interaction model calculations.

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Anastasiia Chekhovska, David Chvátil, Tamara Krasta, Ivana Krausova, Vaclav Olšanský, Daina Riekstiņa, "Photoactivation study of ¹⁶³TB β-decay", RAD Conf. Proc, vol. 7, 2023, pp. 1-5; http://doi.org/10.21175/RadProc.2023.01