Study of the Decay ofTm168to Levels inEr168Using Coincidence and Directional Correlation Techniques

Abstract

The levels in Er/sup 168/ populated by electron capture of Tm/sup 168/ were studied using scintillation spectrometers, gamma-gamma and electron-gamma coincidence measurements, and directional correlation techniques. The following conclusions were reached: the spin and parity of the 1543-kev level are 3-; the 1280-kev transition is El(<0.08% M2); the 721-kev transition is E1(<0.05% M2); and the 743kev transition is E2(<2.4% M1). The attenuation coefficient G/sub 2/ for the 1280 kev-80 kev correlation was determined to be 0.77 plus or minus 0.19 for a source consisting of a dilute aqueous solution of TmCl/sub 3/. The amalysis of the results of the Tm/sup 168/ decay is compared with the predictions using various models. The ratios of reduced transition probabilities for transitions from the gamma vibrational band in Er/sup 168/ are analyzed and a band-mixing parameter z = 0.055 is found. (auth)