Decay of Pm¹⁴⁸

Abstract

The radiations arising from the activities of Pm¹⁴⁸ produced by proton bombardment of Nd¹⁴⁸ (93 % enriched) have been studied mainly by a coincidence scintillation spectrometer. Three gamma rays of 560, 900 and 1460 keV are associated with the 4.2 day activity, while the gamma rays associated with the decay of the 46 day activity are 105, 195, 295, 400, 560, 630, 720, 930, 1015 and 1200 keV, of which 560 and 630 are the most intense and of equal intensity. Beta-gamma and gamma-gamma coincidence experiments show that the main levels in Sm¹⁴⁸ arising from the negaton decay of the 46-day Pm¹⁴⁸ are 560, 1190, 1590, 1910, 2120 and 2205 keV, the highest energy beta-group associated with this activity is 2330 keV which goes to the ground state of Sm¹⁴⁸. A tentative decay scheme is proposed for the 46 day Pm¹⁴⁸ activity.