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Background: 139Pr is located in a transitional region of neutron number close to the N = 82 shell. The study of its high-spin states and collective bands is important for systematically understanding the nuclear structural characteristics in this region. Purpose: To investigate the high-spin levels and to search for oblate bands in 139Pr. Methods: The high-spin states of 139Pr have been studied via the reaction 124Sn(19F,4n) at a beam energy of 80 MeV. The experiment was carried out at the HI-13 Tandem Accelerator at the China Institute of Atomic Energy (CIAE). The data analysis was done by using the &ggr;-&ggr; coincidence method. Results: The level scheme of 139Pr has been expanded with spin up to 45/2ħ. A total of 39 new levels and 45 new transitions are identified. Four collective band structures at high-spin states have been newly established. From systematic analysis, one of the bands is proposed as a double decoupled band; two bands are proposed as oblate bands with &ggr; ∼ -60° another band is suggested as an oblate-triaxial band with &ggr; ∼ --90&dgr;. The other characteristics for these bands are discussed. Conclusions: A new level scheme in 139Pr has been established and the collective bands at high spin have been identified. The result shows that the strong oblate shape-driving effect is caused by neutrons at the high-spin states in 139Pr. [ABSTRACT FROM AUTHOR]

The high-spin states of 141Pm have been investigated through the reaction 126Te(19F,4n) at a beam energy of 90 MeV. A previous level scheme has been updated with spins up to 49/2ħ. Six collective bands at high spins are newly observed. Based on the systematic comparison, one band is proposed as a decoupled band; two bands with strong ΔI = 1 M1 transitions inside the bands are suggested as the oblate bands with γ ∼-60°; three other bands with large signature splitting have been proposed with the oblate-triaxial deformation with γ∼ -90°. The triaxial n-particle-n-hole particle rotor model calculations for one of the oblate bands in 141Pm are in good agreement with the experimental data. The other characteristics for these bands have been discussed. [ABSTRACT FROM AUTHOR]

We report the results of the measurements of complete and incomplete fusion of the 9Be + 169Tm and 187Re systems at energies close to the Coulomb barrier. The activation technique with the detection of offline gamma rays was used to derive the cross sections. By comparing the experimental cross sections with coupled-channel calculations that do not include the breakup channel, we found suppression of the complete fusion of the order of 30% for both systems, at energies slightly above the barrier. This suppression corresponds roughly to the measured incomplete fusion. We also investigate a systematic behavior of the suppression of complete fusion cross sections for 9Be on different targets and we found that it does not depend on the target. [ABSTRACT FROM AUTHOR]

Complete and incomplete fusion cross sections for the 9Be + 181Ta system were measured at near barrier energies, using the offline gamma ray spectroscopy method. The results were compared with coupled channel calculations that do not take into account the coupling of the breakup channel, using a double folding potential as bare potential. A complete fusion suppression of the order of 35% was found, at energies above the barrier, whereas the total fusion cross sections are in agreement with the calculations. The ratio between incomplete fusion and total fusion at energies above the Coulomb barrier was found to be 32 ± 1%. At sub-bamer energies one observes some enhancement of total fusion cross section. [ABSTRACT FROM AUTHOR]

The article presents a study focuses on complete and incomplete fusion in the reaction including Beryllium isotope Be9 and Tantalum isotope Ta181 using offline gamma ray spectroscopy method. The findings include a complete fusion suppression of the order of 35 percent, total fusion cross sections confirming with the calculations and the ratio between incomplete fusion and total fusion at energies above the coulomb barrier.

The article analyzes the complete and incomplete fusion cross sections 9Be + 181Ta reaction using the offline gamma ray spectroscopy method. Topics discussed include comparison through coupled channel calculations excluding the coupling of the breakup channel, varying ratio of the incomplete and total fusion at energies above the coulomb barrier along with the total fusion comprising the sum of complete and incomplete fusion.

The article discusses the study conducted to examine the difference between the complete and incomplete fusion in the Beryllium and Tantalum reaction at near barrier energies using the offline gamma ray spectroscopy method. It mentions that results were compared with coupled channel calculations using a double folding potential as bare potential. It also presents the comparison of the data with coupled channel (CC) calculations.

The article presents a study on the measurement of complete and incomplete fusion cross sections for the 9Be + 181Ta system near barrier energies using the offline gamma ray spectroscopy method. Topics discussed include experiments on fusion cross sections of weakly bound nuclei, study of reactions of both stable and radioactive weakly bound nuclei, and detection alpha particles emitted in the decay of residual nuclei.

The article presents a study focusing on complete and incomplete fusion in the reaction of isotopes of beryllium (Be) and Tantalum (Ta) using offline gamma ray spectroscopy method. The findings include a complete fusion suppression of the order of 35 percent, total fusion cross sections confirming with the calculations, and the ratio between incomplete fusion and total fusion at energies above the coulomb barrier.

High-spin states of Pt190 have been reinvestigated using the 176Yb(18O, 4n) reaction at a beam energy of 88 MeV. The previously known positive parity band associated with the νi13/2-2νh9/2-1νj-1 (νj being νp3/2 or νf5/2) configuration has been revised and extended significantly. A new negative parity band has been established and proposed to be based on the νi13/2-3νj-1 configuration. Possible structure evolution of the yrast line from predominantly vibrational to rotational with increasing spin is discussed with the help of Eγ over spin curves. Additionally, calculations of total Routhian surfaces have been performed to investigate the band properties. [ABSTRACT FROM AUTHOR]

High-spin level structures of the near-spherical nuclei 9l,92Zr have been reinvestigated via the 82Se(13C, xn) (x =4,3) reactions at a beam energy of 44 MeV. By the use of in-beam spectroscopic methods, 13 new transitions belonging to 9lZr and 19 to 92Zr have been observed and the level schemes of 9K92Zr have been extended up to Ex ≈ 11 MeV excitation energy. The newly constructed level schemes are characterized by the 88 Sr core breaking, and the proton P3/2-P1/2 energy gap in 92Zr is obviously reduced compared with 9lZr when one more neutron goes into the (d5/2/g7/2) orbital. [ABSTRACT FROM AUTHOR]

We have measured the complete fusion, incomplete fusion, and the one-neutron stripping reaction for the 9Be+186W system, at energies not too much above the Coulomb barrier. The online and offline gamma ray spectroscopy methods were used for the derivation of the cross sections. A large value of one-neutron stripping cross section has been observed. The comparison of the data with coupled channel calculations without taking into account the breakup and transfer channels show the usual complete fusion suppression. The possible suppression of the total fusion is discussed. [ABSTRACT FROM AUTHOR]

High-spin states in the odd-odd 194Au nucleus have been investigated using the 192Os(7Li, 5n) reaction at a beam energy of 44 MeV. The previously known structures built on the πh11/2-1⊗vi13/2-1 and πh11/2-1⊗ vi13/2-2vj configurations are extended to high-spin states, and a new Iπ = (20+) state associated with the πh11/2-1⊗vi13/2-2vh9/2-1 configuration is identified. Importantly, the πh11/2-1⊗vi13/2-2 band is found to exhibit normal signature splitting. The experimental results are compared with predictions from total Routhian surface and cranked shell-model calculations. Nonaxial shapes for the πh11/2-1⊗vi13/2-2 and πh11/2-1⊗vi13/2-2vh9/2-1 configurations are proposed. Possible reasons for the absence of signature inversion in the πh11/2-1⊗vi13/2-2 band in 194Au are discussed. [ABSTRACT FROM AUTHOR]

The high spin states .of 106Pd have been investigated with in-beam γ-ray spectroscopic methods using the l00Mo(11B, lp4n)106Pd reaction at a beam energy of 60 MeV. All earlier known bands were extended considerably and additional bands were identified. The configurations of these bands are discussed on the basis of the experimental aligned angular momenta and total Routhian surface calculations. Both two-quasineutron and two-quasiproton structures have been found in 106Pd. The nonyrast low-lying positive-parity band was interpreted as a γ-vibrational band. [ABSTRACT FROM AUTHOR]

Excited states in l95Au have been studied experimentally via the l92Os(7Li, 4n) reaction at a beam energy of 44 MeV. Based on the &ggr;-&ggr;-t coincidence measurement, a level scheme consisting of 15 new transitions and 10 new levels is established for l95Au. The triaxial shape-polarizing effect of the high-j h11/2 proton hole was studied by total Routhian surface calculations. By comparing with the level structures in the odd-A Au isotopes and the even-even core Hg nuclei, configurations are proposed to the rotational bands and three-quasiparticle states observed in 195Au. [ABSTRACT FROM AUTHOR]

High-spin states in 139Pm are investigated via the 116Cd(27A1, 4n)139Pm fusion-evaporation reaction at a beam energy of 120 MeV. The previously reported level scheme has been modified because of identifications of some linking and doublet transitions. The revised yrast πh11/2 band obviously undergoes πh11/2 → π(h11/2)³ → π(h11/2)³ ⊗ πh11/2 ⊗ ν(h11/2)-2 band crossings at ħω = 0.45 and 0.39 MeV. Two negative-parity dipole bands have been assigned as π(h11/2) ⊗ ν(h11/2)-2 and πh11/2 ⊗ ν(h11/2)-4 configurations, respectively, can be considered as examples of magnetic rotational bands. [ABSTRACT FROM AUTHOR]

Excited states in the stable nucleus 193Ir have been investigated through an in-beam γ-ray spectroscopic technique following the 192Os(7Li, α2n) reaction at a beam energy of 44 MeV. A level scheme built on the πh11/2 isomer has been extended to high-spin states using eleven newly observed γ transitions. The πh11/2 band is proposed to be formed by coupling an h11/2 proton to a core with large triaxial deformation. Three-quasiparticle states are suggested in 193Ir on referring to the similar states in 187Ir. The features of signature splitting in the πh11/2 bands of 187-193Ir are discussed with the help of total Routhian surface calculations. [ABSTRACT FROM AUTHOR]

High-spin levels of the neutron-rich 114Ru have been investigated by measuring the prompt γ rays in the spontaneous fission of 252Cf. The ground-state band and one-phonon γ-vibrational band have been extended up to 14+ and 9+, respectively. Two levels are proposed as the members of a two-phonon γ-vibrational band. A back bending (band crossing) has been observed in the ground-state band at ℏω≈ 0.40 MeV. Using the triaxial deformation parameters, the cranked shell model calculations indicate that this back bending in 114Ru should originate from the alignment of a pair of h11/2 neutrons. Triaxial projected shell model calculations for the γ-vibrational band structures of 114Ru are in good agreement with the experimental data. However, when using the oblate deformation parameters, both of the above-calculated results are not in agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The high spin states of 112In have been investigated with in-beam γ-ray spectroscopic methods using the 110Pd(7Li,5n)112In reaction at a beam energy of 50 MeV. A level scheme with three band structures has been established and their configurations are discussed. The positive-parity dipole band has been assigned as a magnetic rotation band. Particle-rotor model calculations have also been performed to interpret the rotational structures in 112In. [ABSTRACT FROM AUTHOR]

The new neutron-deficient isotope 216U was produced in the complete-fusion reaction 180W(40Ar,4n)2l6U. The evaporation residues were separated from the primary beam in flight by the gas-filled recoil separator Spectrometer tor Heavy Atoms and Nuclear Structure. The activities have been identified by the α-α position and time correlation measurements. Two cc-decaying states with Ea = 8384(30) keV, Tl/2 = 4.72+4.72-1.57 ms for the ground state and E&3945; = 10582(30) keV, T1/2 = 0.741.34-0.29 ms for an isomeric state were identified in 216U. [ABSTRACT FROM AUTHOR]