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Excited states in Cs137 have been studied by using the near-barrier, single-proton transfer reaction B10(Xe136,Be9γ)Cs137 in inverse kinematics and performing particle-γ and particle-γγ coincidence measurements. The low-spin level scheme of Cs137 has been augmented: (i) The expected set of single-proton, seniority υ=1 states has been delineated in its entirety; (ii) Another member of the υ=3 proton 0g7/2 multiplet, a low-lying 9/2+ level, has been identified and this set of states now approaches completion; (iii) A second 9/2+ and a candidate 13/2+ level have been observed. The results are discussed in the framework of shell-model calculations in the proton 2s1d0g0h shell.

Excited states in Xe-137 have been studied by using the near-barrier single-neutron transfer reactions C-13(Xe-136, C-12 gamma) Xe-137 and Be-9(Xe-136, Be-8 gamma) Xe-137 in inverse kinematics. Particle-gamma and particle-gamma gamma coincidence measurements have been performed with the Phoswich Wall and Digital Gammasphere detector arrays. Evidence is found for a 13/2(2)(+) level (E = 3137 keV) and for additional high-lying 3/2(-) and 5/2(-) states. The results are discussed in the framework of realistic shell-model calculations. These calculations are also extended to the 13/2(1)(+) and 13/2(2)(+) levels in the N = 83 isotonic chain. They indicate that there is a need for a value of the neutron 0i(13/2) single-particle energy (E-SPE = 2366 keV) lower than the one proposed in the literature. It is also demonstrated that the population patterns of the j = l +/- 1/2 single-particle states in Xe-137 are different for the two targets used in these measurements and the implications of this effect are addressed.