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The decay of M Am has been studied by observing a-y coincidences using Si (Au) surface-barrier and Ge (Li) detectors in conjunction with a 4096-channel two-parameter analyzer, y rays of 31.2, 43.6, 50.6, 55.4, 74.8, 86.7, 117.8, 142.0, 169, 195, and 220 keV were observed. Only the 43.6-, 74.8-, and 117.8-keV y rays have been previously reported. These results confirm many features of the previously accepted level scheme of the 239 Np daughter. Furthermore, new levels at 72 and 123 keV have been found which are apparently the f-f and ^+ members, respectively, of the ground-state rotational band. These energies agree well with predictions based on the collective model. The intensity ratio of a groups to the ground and first excited states has been measured to be 1.17, in poor agreement with a theoretical estimate of 2.03.

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