Neutron hole states in 137Ba, 139Ce, 141Nd and 143Sm

Structure of N=81144Eu from the decay of144Gd

“…The respective 2 +, 3 + and 4 + states from the coupling of (7cd5/2 vd3/2) are consistent with those deduced from the present work for the first three excited states. These levels together with the ground state would form a multiplet linked by M1 transitions, which is also consistent with the empirical rule concerning transitions between members of the same multiplet [29]. The first 2 + state in the neighboring even-even nuclei is known to drop from about 1500 keV to 700 keV between N = 82 and N = 80.…”

Neutron hole states in theN=81 nuclei

“…Experimentally extracted centroid energies by Jolly and Kashy [4] and Chaumeaux et al [5], do not show the same dependence on the number of protons. The systematic reduction in spacing between the 2(/3/2 and 3s~/2 neutron hole levels as obtained by Chaumeaux is not reproduced in the recent experiment of Jolly.…”

“…The best-fit parameters Aj and ~ that were determined from the iteration procedure, are given in Table 1, together with the centroid energies as obtained from the work of Jolly and Kashy [5] and of Schneid and Rosner [12] for the 2ds/z neutron-hole state in i35Xe. Also the values of h co, taken from the neighbouring N= 82 nuclides, are given in Table 1.…”

“…Core excitations of up to three quadrupole phonons should be sufficient to describe nuclear states in the odd neutron N=81 nuclei up to 2 MeV. For many of the N=81 nuclei, neutron pick-up reactions have been performed in a systematic way by Jolly and Kashy [4] and Chaumeaux et aL [5]. These data on the distribution of the single-hole strength give extra information in addition to that from the beta-decay and subsequent gamma-decay, as has been obtained for 133Te (Ref.…”

The internal conversion of theN=81 Isotones139m Ce and141m Nd

“…Shell model calculations for the transitions between haa/2 and d3/2 single hole levels have been performed extensively [3,4], and a qualitative description of the systematic changes in transition energy and transition probability was delivered. The single hole character of some of the levels was established by stripping reactions [5,6]. Conversion data confirmed the M4 characterization for transition in 139Ce and ~4~Nd within approximately 12% [-7, 8].…”