Properties of 152Gd collective states
Abstract.The decays of 152Tb (T1/2 = 17.5 h) and 152Gd excited states have been investigated by the analysis of $\gamma$-rays and $\gamma\gamma$-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 $\gamma$-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 ${\rm EC}/\beta^ + $ ratio was found for a number of low-lying levels, for most of the levels their spins, parities, and $\log ft$ are given. The excited levels of 152Gd were deduced from the analysis of $\gamma\gamma$-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.