Proton states in theN = 86 nuclei147Pm and149Eu populated in the (3He,d), (α,t) and (t, α) reactions

The (³He,d) and (α, t) reactions on targets of¹⁴⁶Nd and¹⁴⁸Sm have been studied, using beams of 24 MeV³He and 27 MeV⁴He from the McMaster University tandem van de Graaff accelerator. Also the (t, α) reaction on a target of¹⁴⁸Sm has been studied, using 17 MeV tritons from the Los Alamos Scientific Laboratory tandem accelerator. The reaction products were analyzed with magnetic spectrographs. Information on thel-values was obtained from (³He,d) angular distributions and from ratios of (α,t) and (³He,d) cross sections. In each nucleus a severe fragmentation of the shell-model strength is found. In particular a total of 13(7)l=2 transitions and 6(6)l=0 transitions have been identified in¹⁴⁷Pm(¹⁴⁹Eu). The results are analyzed in terms of the spherical shell model, which accounts fairly well for the summed spectroscopic strengths. However, with the existence of the (t, α) data a more detailed investigation of the emptiness of individual levels observed in¹⁴⁷Pm gives some indication that a deformed scheme might be more successful in describing these nuclei.