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The neutron-deficient 119 Ba nucleus has been studied using the 58 Ni( 64 Zn, 2pn) reaction and the JUROGAM 3 γ -ray detector array coupled to the MARA recoil-mass separator setup. One new rotational band and several low-lying states are newly identified. A half-life of T 1/2 = 0.36(2) μs has been measured for the 5/2 − bandhead of the νh 11/2 band. The two previously known rotational bands are confirmed, except for the higher part of the +1/2 signature partner of the positive-parity band. Configurations are assigned based on the analysis of the observed quasiparticle alignments whose nature is unveiled by the calculations using the particle number conserving cranked shell model.

Low-spin states of 157 Dy have been studied using the JUROGAM II array, following the 155 Gd (α, 2n) reaction at a beam energy of 25 MeV. The level scheme of 157 Dy has been expanded with four new bands. Rotational structures built on the [523]5/2and [402]3/2 + neutron orbitals constitute new additions to the level scheme as do many of the inter-and intra-band transitions. This manuscript also reports the observation of cross I + → (I-1)and I -→ (I-1) + E1 dipole transitions inter-linking structures built on the [523]5/2 -(band 5) and [402]3/2 + (band 7) neutron orbitals. These interlacing band structures are interpreted as the bands of parity doublets with simplex quantum number s = -i related to possible octupole correlations.Two previous experiments conducted with large Ge detector arrays used heavy-ion induced reactions 150 Nd( 12 C,5n) and 124 Sc( 36 S,3n) [71,72,97] to study the medium to high-spin states of 157 Dy. These experiments reported rotational bands built on the h9/2[521]3/2 -, i13/2[651]3/2 + and h11/2[505]11/2neutrons configurations but reported no transitions linking these structures. To this end we have performed in-beam measurements using the JUROGAM II array to study the rotational bands of 157 Dy and to search for evidence of octupole correlations. We report on four new bands as well as many new linking transitions relative to the previously observed structures.The rotational behaviour of the new bands is described in terms of quasi-particle assignments, and the observed alignment properties are analyzed within the framework of the cranked shell model. II. Experimental details and analysisExcited states of 157 Dy were populated using the 155 Gd (α, 2n) reaction at a beam energy of 25 MeV. The 155 Gd target was 0.98 mg/cm 2 thick with a purity of 91%. Gamma-rays following the fusion evaporation reaction were detected with the JUROGAM II multi-detector array [73] in JYFL, Jyväskylä, Finland. The spectrometer setup comprised 39 high-purity germanium detectors, all with BGO escape suppression shields; 15 EUROGAM coaxial detectors (Phase 1 [75] and GASP [74] type) and 24 EUROGAM Phase II clover detectors [76]. Approximately 14 x 10 9 γ-γ events were unfolded from the data in the off-line analysis and replayed into γ-γ Radware [77, 78] coincidence matrices, which were used to construct the level scheme of 157 Dy. The spins and parities for the new rotational structures were successfully assigned using the Directional Correlation from Oriented States (DCO ratios/RDCO) [79, 80] and linear polarization anisotropy (Ap) methods [81]. While Ap is given as used in [82], the DCO matrices were constructed using data from detectors in the rings at 158° and 86°+94°, thus the RDCO for the JUROGAM II array in this work is; RDCO = I γ1(at 158º : gated on γ2 near 90 º) / I γ1(near 90º : gated on γ2 at 158º)

The very neutron-deficient strongly deformed 119 Cs nucleus has been studied using the 58 Ni( 64 Zn, 3p) reaction and the JUROGAM 3 γ -ray detector array coupled to the MARA recoil-mass separator setup. The excitation energies of all observed bands have been determined, spins and parities have been firmly assigned to most of the observed states. The previously known and the newly identified rotational bands have been extended to very high spin and excitation energy. The configurations of the observed bands are discussed using the particle number conserving cranked shell model. The present study establishes the largest set of rotational bands observed in the proton-rich A ≈ 120 mass region.

The jurogam 3 spectrometer has been constructed for in-beam γ-ray spectroscopy experiments in the Accelerator Laboratory of the University of Jyväskylä, Finland. jurogam 3 consists of germanium-detector modules in a compact geometry surrounding a target to measure γ rays emitted from radioactive nuclei. jurogam 3 can be employed in conjunction with one of two recoil separators, the mara vacuum-mode separator or the ritu gas-filled separator, and other ancillary devices.