Eur. Phys. J. A (2003) 18: 605-626
https://doi.org/10.1140/epja/i2002-10167-8

Properties of ¹⁵² Gd collective states

¹ Joint Institute for Nuclear Research, Dubna, Russia
² Nuclear Physics Institute ASCR, CZ-25068, Řež, Czech Republic

^* e-mail: Vitali.Pronskikh@jinr.ru

Abstract

The decays of ¹⁵²Tb (T _1/2 = 17.5 h) and ¹⁵²Gd excited states have been investigated by the analysis of -rays and -coincidences measured with the use of high-resolution HPGe detectors. The source of ¹⁵²Tb was prepared by chromatographic isolation followed by electromagnetic separation from a tantalum target irradiated by an internal proton beam of the LNP JINR phasotron. New and more precise data on the -transitions and excited states of ¹⁵²Gd are reported. Using previously published data on internal-conversion electrons many transition multipolarities are suggested, some of them with E0 admixture. The ratio was found for a number of low-lying levels, for most of the levels their spins, parities, and are given. The excited levels of ¹⁵²Gd were deduced from the analysis of -coincidences. The experimental level energies and reduced transition probabilities are compared with the calculations by phenomenological formulae as well as in the frameworks of theoretical models.