[en] Odd Pm isotopes have been studied by one proton pick-up and stripping reactions. Spin assignment and spectroscopic factors have been obtained for a number of energy levels. In the stripping reactions, the relative cross-sections have been measured with an unusually high precision by the use of a target of natural neodymium. The spectroscopic strengths have been extracted using standard distorted wave methods. The nuclear structures of these promethium isotopes fall into three categories. The spherical approach seems valid for ¹⁴³Pm and ¹⁴⁵Pm and the deformed regime covers ¹⁵¹Pm and ¹⁵³Pm, while ¹⁴⁷Pm and ¹⁴⁹Pm remain as transitional nuclei. (Auth.)

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[en] The (tau,d) and (α,t) reaction on targets of ¹⁴⁸Nd, ¹⁵⁰Sm and ¹⁵²Gd have been studied, using beams of 24 MeV ³He and 27 MeV ⁴He from the McMaster University FN tandem Van de Graaff accelerator. The reaction products were analyzed with a magnetic spectrograph and detected with photographic emulsions. The (α,t) spectra were measured at two angles for each target, and the (tau,d) reactions were studied at 8 or 9 angles. The l-values for a number of low-spin states were determined from the (tau,d) angular distributions, and ratios of the (α,t) and (tau,d) cross sections were used to obtain l-values for several other states. There are some striking similarities in the observed structures of the three final nuclei, ¹⁴⁹Pm, ¹⁵¹Eu and ¹⁵³Tb. In each case there are low-lying strongly populated 11/2^- states and a higher lying l=5 level somewhat below 1 MeV excitation energy. Several states (10 in ¹⁴⁹Pm, 17 in ¹⁵¹Eu and 8 in ¹⁵³Tb) appear to be populated via l=2 transitions, and these are strongly excited 1/2⁺ levels at >= 1 MeV of excitation energy in each case. Of particular interest is a 7/2^- state located <= 50 keV above the lowest 11/2^- state in each nuclide. The relatively strong populations of these 7/2^- levels in the present experiments are contrary to expectations based on the simple shell model as there are no fsub(7/2) states in the 50< Z<82 shell. (Auth.)

[en] The ¹⁴⁸Nd(d,t)¹⁴⁷Nd reaction has been studied using 12 MeV deuterons. The present results confirm previous indications that the highest energy proton group found in an early ¹⁴⁶Nd(d,p) investigation does not correspond to the ground state transition, but to the level at an excitation energy of 50 keV. The (d,t) angular distributions were used to determine l-values for a number of transitions. A striking similarity is noted with the energy levels and spectroscopic strengths previously found in the isotones ¹⁴⁹Sm and ¹⁵¹Gd. With the exception of the hsub(11/2) state, it is possible to explain the observed strengths in terms of the spherical shell model, although there is fragmentation of the spherical states. (author)

[en] The (³He,d) and (α,t) reactions have been used to study odd proton states in sup(157,159,161,163)Ho. Information on the l-values was obtained from the ratios of (³He,d) and (α,t) cross sections and from (³He,d) angular distributions. The results are interpreted in terms of the Nilsson model with pairing and Coriolis mixing included. Nuclear structure factors were extracted from the experimental data with the aid of DWBA calculations. (author)

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[en] The (³He, d) and (α, t) reactions on targets of ¹⁴⁶Nd and ¹⁴⁸Sm have been studied, using beams of 24 MeV ³He and 27 MeV ⁴He from the McMaster University tandem van de Graaff accelerator. Also the (t, α) reaction on a target of ¹⁴⁸Sm has been studied, using 17 MeV tritons from the Los Alamos Scientific Laboratoy tandem accelerator. The reaction products were analyzed with magnetic spectrographs. Information on the l-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 in ¹⁴⁷Pm(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 in ¹⁴⁷Pm gives some indication that a deformed scheme might be more successful in describing these nuclei. (orig.)

[en] The (d,t) and (³He,α) reactions on a target of ¹⁵⁶Dy have been used to study the nuclear structure of ¹⁵⁵Dy. The (d,t) angular distributions and ratios of the (³He,α) and (d,t) cross sections were used to determine l values for a number of transitions. It is found that the positive parity states can be described in terms of the Nilsson model when Coriolis coupling is included while for the negative parity states only the gross features are well-described this way. (author)