Decay of Eu¹⁴⁸

Abstract

The level structure of Sm–148, which is near the neutron closed shell 82, has been studied by the analyses of the radiations from the decay of Eu–148 (54 days) with various scintillation spectrometers. The single and the coincidence measurements were made by means of 3''×3'' and 2''×2'' NaI(T1) crystals, and the 5''×4'' well type NaI(T1) crystal was also used for searching the level population in the Sm–148 nucleus. Spins of the levels were determined using the gamma-gamma directional correlation method. The following levels has been proposed for Sm–148; 555(2+), 1183(4+), 1470(1), 1598(3), 1735(4+), 1911(3 or 4), 2148, 2220, 2460, 2500, 2740, 2830, 3100 and 3370 keV. The results are compared with the predictions of various models of even-even nuclei.