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[en] The nucleus ¹⁴¹Gd has been investigated at high spins for the first time following the reactions ¹¹²Sn(³²S,2pn)¹⁴¹Gd at 155 MeV and ¹¹²Sn(³³S,2p2n)¹⁴¹Gd at 170 MeV. The methods of in-beam γ-ray spectroscopy were used to establish a number of different structures, including a band which has been assigned as being based on the νi_13/2[660]1/2⁺ Nilsson intruder orbital. This is the heaviest nucleus thus far in which this type of intruder band has been identified. (author). 11 refs., 3 figs

[en] The β/γ and delayed proton decays of mass separated A=141 isotopes with Z=63--66 were investigated with an on-line mass separator. Branching ratios have been redetermined for the total β decay of the 2.7(3) s, (11/2)^- isomer ¹⁴¹Eu^m at 96.5 keV (13_-2⁺⁴%), and for the direct β feeding of the 1.58 keV (3/2)⁺ level of ¹⁴¹Sm in the decay of 40-s ¹⁴¹Eu^g [73(5)%]. Detailed decay schemes have been constructed for the decays of the (11/2)^- isomer ¹⁴¹Gd^m [11(2)% isomeric transition] and the (1/2)⁺ ground state, ¹⁴¹Gd^g. Half-lives of 24.5(5) s and 14(4) s, respectively, have been determined for these isomers. A delayed proton branch of 0.03(1)% was identified in the decay of ¹⁴¹Gd^g. A detailed decay scheme was also constructed for 3.5(2)-s ¹⁴¹Tb and a J^π=(5/2^- ) was assigned to its ground state, at variance with the systematics of heavier, odd-mass Tb isotopes. All γ-ray assignments to the various isotopes are based on xγ and γγ coincidences and on half-life measurements. A 0.9(2)-s half-life for ¹⁴¹Dy was determined from its delayed proton decay. All spin assignments proposed in this paper are discussed in terms of Nilsson level diagrams and nuclear shapes

[en] The nucleus ¹⁴¹Gd was investigated at high spins for the first time via the reactions ¹¹²Sn(³²S,2pn)¹⁴¹Gd at 155 MeV and ¹¹²Sn(³³S,2p2n)¹⁴¹Gd at 170 MeV. The methods of in-beam γ-ray spectroscopy were used to establish a number of different structures. These include a band assigned as the νi_13/2[660]1/2⁺ intruder in the Nilsson scheme. This is the heaviest nucleus thus far in which this type of intruder band has been identified, and is the first case in which the 13/2⁺ bandhead has been clearly observed. Cranked shell model (CSM) calculations predict the occurrence of backbends due to h_11/2 proton and h_9/2 neutron band crossings. Gradual upbends are observed in the experimental alignments, which suggests the interaction strengths are stronger than those predicted by the CSM

[en] Nuclear spectroscopic information for experimentally investigated nuclides of mass 141 (Te, I, Xe, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, and Ho) has been evaluated. A summary of information obtained in various reaction and decay experiments is presented, together with data tables and adopted level schemes

[en] Proton rich exotic nuclei of rare-earth have been identified and their low-energy structure studied with the system of He-jet fed on-line mass separator recently put into operation at the SARA accelerator. In order to investigate the triaxial stability of the deformed ground states in the e-e exotic Samarium isotopes, lattice Hartree-Fock + BCS calculations have been performed

[en] This progress report of the Physics section of Chalk River Nuclear Laboratories highlights work on major equipment: 1) Tandem Accelerator Superconducting Cyclotron (TASCC), 2) Isotope Separator On Line (ISOL), 3) Spectrometer Array for Particles Produced in Heavy Ion Reactions (SAPPHIRE), and 4) The Double Neutron Spectrometer for neutron scattering (DUALSPEC). Theoretical physics work includes fractal theory, non-topological soliton model of the nucleons, meson currents in relativistic shell model theories and supergravity. Progress of the Sudbury Neutrino Observatory (SNO) and the National Fusion Program (NFP) is discussed. Two commercial aspects are included; the formation of Shar-Buc Enterprises, the first spin-off business of the Research Company and the Applied Neutron Diffraction for Industry (ANDI), a major commercial activity

[en] Excited states above the 11/2^- isomer have been identified for the first time in the neutron deficient ¹⁴¹ Gd nucleus. The level sequence built on the 11/2^- isomeric state was constructed using y-ray spectroscopy methods. The new data are compared with level patterns in neighbouring nuclei. (orig.)

[en] Several new measurements of proton emission decay isotopes are reported. Protons were measured in coincidence with positrons, gammas and x-rays. Isotopes were produced by 200-500 MeV heavy ion fusion reactions. Half-lives are reported for dysprosium, gadolinium, cerium, neodymium and lanthanum isotopes and representative cerium proton spectra are shown

[en] Several new β-delayed proton precursors were produced in (HI; xn, yp) reactions at the LBL SuperHILAC and studied with the isotope separator OASIS. Unambiguous Z-identifications were obtained in all cases by observing characteristic X-rays coincident with the protons. Ground state spins were determined infavorable cases. The lowest 2⁺ levels in the rotational bands of ¹²⁶Ce and ¹³⁰Nd were confirmed. (orig.)