Experimental research of isomer states of even-odd nuclei Tm155, Lu157 and of excited states of odd isotopes Gd147,153

A complex of physical installations developed for spectroscopic investigations of short-lived isotopes and working on the line of the proton beam of the JINR phasotron is briefly described. The alpha-decay of 155Tm was investigated. Two components of 155Tm alpha-decay desintegration curve with T1/2=23(3)s and T1/2=47(6)s for Eα=4462 keV have been observed. It was concluded that ground state of 155Tm has spin and parity 11/2- and T1/2=23(3)s and isomeric one with 41(6) keV - 1/2+ and T1/2=47(6)s. The new low spin isomeric state of 157Lu with T1/2 9.6(8)s and Eα=4295(5) keV was found. The investigations of 147Gd excited states populated at 147Tb decay were continued. Decay scheme of 147Tb containing 38 excited levels is proposed. Their (ε + β+) and logft have been determined. The stucture of the excited states of 147Gd is discussed. Energies and intensities of gamma-rays observed in the decay of 153Tb have been measured more precisely. Internal conversion electrons of 53.6 keV gamma-transition was observed.The multipolarity M2 of 53.6 keV transition was concluded. On the basis of investigations of γ-rays and eγ-coincidences the 153Tb decay scheme including 56 excited states was obtained more precisely and their structure is discussed. (author). 12 refs