On Decay of ¹⁰⁶Rh

The lower levels of the nucleus ¹⁰⁶₄₆Pd₆₀ are explained quite well in terms of the vibrational model. The first excited level of this nucleus with the characteristics 2⁺ can be considered as a one-phonon vibrational state, and the three following ones - 2⁺, 0⁺ and 4⁺ - as a two-phonon triplet. A detailed study of the properties of the excited levels of ¹⁰⁶Pd allows us to more accurately determine the parameters of the vibrational model and explain the nature of higher levels. The source was the radioactive isotope ¹⁰⁶Rh (T_1/2 = 30 sec), which was in equilibrium with the parent ¹⁰⁶Ru (T_1/2 = 366 days) – a product of uranium fission. The spectrum of internal conversion electrons was studied on a β-spectrometer with double focusing with a resolving power of 0.17%, γ-rays – on a semiconductor γ-spectrometer with a coaxial Ge(Li) detector with a volume of 5 cm³ and a resolving power of ≈5 keV. The energies of the two most intense transitions, 511.0±0.2 and 622.0±0.2 keV, were determined from conversion electrons. The reference points were the electron lines of the radioactive sediment of thorium and ¹³⁷Cs.