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Multiple Coulomb-excitation experiments for 156Gd were made with a 118 MeV 32S beam and a 225 MeV 58Ni beam. The ground-state band, the β band (K = 0+), another K = 0+ band, and the γ band (K = 2+) were observed up to the 18+, 14+, 8+, and 12+ states, respectively, while the octupole band (K = 1-) was observed up to the 15- state, through the analysis of particle-γ-γ data. Compared with the results of the in-beam γ-ray spectroscopy previously obtained, the present result suggests that a band crossing occurs in the γ band. As for the β band, the excitation energy of the 12+ state was revised and the 14+ state was newly observed in the present experiment. The intrinsic matrix elements entering the generalized intensity relations were obtained so as to reproduce the spin dependence of the E2 matrix elements extracted from the experimental results of particle-γ angular correlation for the transitions within each band and between each band and the ground-state band by the least-squares search code gosia. The change of characters in the β and γ bands is discussed as a possible cause for the variation of the E2 matrix elements in the higher-spin region. The intrinsic matrix elements were also obtained for the E1 and E3 transitions from the ground-state band to the octupole band with K = 1- through analysis by GOSIA. [ABSTRACT FROM AUTHOR]

High-spin states of 159Dy have been studied by using reaction 150Nd(13C, 4n). Two rotational bands based on the configurations ν[521]3/2 and ν[642]5/2 have been extended to 57/2− and 61/2+ states, respectively. A neutron AB crossing has been observed around ℏω=0.26 MeV in the ν[521]3/2 band. It has been observed that the signature splitting is inverted after the band crossing in the ν[521]3/2 band. The first band crossing has been observed around ℏω=0.38 MeV in the ν[642]5/2 band. Seven E1 transitions from the ν[521]3/2 band to the ν[642]5/2 band have been observed and discussed on the base of Generalized Intensity Relation. It is found that the B(E1)/B(E2) ratios for 47/2− and 43/2− states become enhanced relatively to those for the lower-spin states. [Copyright &y& Elsevier]

Lifetime measurements were made for the vh11/2 band in 101Pd, which had been interpreted as a possible antimagnetic rotation band based on the comparison of I-ω behavior with the calculation of a semiclassical particle-rotor model in our previous study. Doppler broadened line shapes were analyzed for the decaying γ rays in the band following the reaction 68Zn(37Cl,1p3n)101Pd. The semiclassical particle-rotor model was modified to reproduce both the I-ω plot and the B(E2) behavior simultaneously for the antimagnetic rotation bands in Pd and Cd nuclei, for which B(E2) values had been measured sofar. Reasonable agreements between the experiment and the calculation were obtained. It is concluded that the lower part of the vh11/2 band in 101Pd can be interpreted as an antimagnetic rotor. [ABSTRACT FROM AUTHOR]

High-spin states of "Rh were studied through in-beam y-ray spectroscopy by using the reaction 68Zn(37Cl, u2n). The upper part of the band based on the g9/2 proton orbital was rearranged in four parallel cascades. Negative parity was tentatively assigned for the side-band that previously had no parity assignment. This negative-parity band was interpreted as having the configuration of π (g9/2)5v[(5/2g7 /2) (h ll / 2)] and extended up to 51(-)/2 ( which is possibly a terminating state. The band based on the p1/2 proton orbital was observed up to 29-/2and its property was compared with those of neighboring odd-Z nuclei from the two different viewpoints, one of which is a weakly deformed soft rotor with spin alignments and the other is vibrational to rotational evolution along the band. [ABSTRACT FROM AUTHOR]

High-spin states of 101Pd were studied through in-beam y-ray spectroscopy by using the reaction 68Zn(37Cl, lp3n). The band based on the vh11/2 neutron orbital was extended up to ( y ), and the band based on the d5/2 neutron orbital was revised. Various transitions decaying to these bands were observed, and consequently several side bands were established. Electric dipole transitions from the vh11/2 band to the vd5/2 band were also observed. The structure of the Απ/2 band is discussed from the viewpoint of antimagnetic rotation based on a semiclassical particle-rotor model by taking neutron alignments into account. The possible existence of octupole correlations is also discussed on the basis of B(E\)/B(E2) ratios for the decays of the vh11/2 band. [ABSTRACT FROM AUTHOR]

High-spin states in the odd-odd 174Re have been investigated via the 152Sm(27Al, 5ny)174Re reaction with the help of excitation function, x-γ, and γ-γ coincidence measurements. Five rotational bands have been observed and their configurations were assigned based on alignments, band crossing frequencies, electromagnetic properties, and the estimated bandhead excitation energies. Low-spin signature inversion has been identified in the two-quasiparticle bands built on πh11/2 ⊗ vi13/2, πh9/2 ⊗ vi13/2, and π ½-[541] ⊗ v5/2-[512] configurations. E2 interband transitions were analyzed with band-mixing calculations giving information on shapes and shape driving effects for the bands of interest. [ABSTRACT FROM AUTHOR]

The article presents the experimental developments in nuclear physics. It presents the study which investigated the high-spin states in the odd-odd 174rhenium (Re) through the 152samarium (Sm)(27Aluminum (Al), 5nϒ)174Re reaction. It cites the identification of five rotational bands, with their configurations assigned based on alignments, band crossing frequencies and electromagnetic fields, among others.

The quadrupole shape evolution in heaviest stable Mo isotopes is studied in terms of the shape coexistence phenomenon occurrence in this region of nuclear chart. Quadrupole deformation parameters of the 96,98,100Mo isotopes in the low-lying (ground and excited) 0+ states were deduced using Coulomb excitation method. In all cases rich sets of electromagnetic reduced matrix elements were determined using the GOSIA code and then analysed using the Quadrupole Sum Rules formalism. Discussion of the experimental results in comparison with the predictions of microscopic calculations within the general quadrupole collective Bohr Hamiltonian model is presented for 100Mo. [ABSTRACT FROM AUTHOR]

Coulomb excitation experiments were performed with 96Mo, 98Mo and 100Mo isotopes using both beam and target excitation. As a result, quadrupole deformation parameters were deduced for two lowest-lying (ground and excited) 0+ states. Surprising shape changes of these states were observed. [ABSTRACT FROM AUTHOR]

Coulomb excitation experiment was carried out with a 68Zn beam bombarding a natPb target. Two E2 matrix elements and the quadrupole moment of the 21+ state were newly derived with the least-squares search code GOSIA. The potential energy surface (PES) was calculated with the Nilsson–Strutinsky model, showing two shallow minima: the first minimum does not contain the 1g9/2 orbit below the Fermi surface, while the second minimum does. The ground state band and the intruder band seem to be constructed on the first and the second minimum, respectively. As for the ground state band, the asymmetric rotor model and the IBM in O(6) limit reproduced the experimental values rather well. The shallow PES may suggest instability of the shape. The ground state band structure may be explained assuming a soft triaxial deformation. [Copyright &y& Elsevier]

A Coulomb excitation experiment was carried out with a 66Zn beam bombarding a matPb target. Four E2 matrix elements and the quadrupole moment of the 2+1 state were derived with the least-squares search code GOSIA. According to the B(E2) values, the ground band can be interpreted as a quasirotational band. It was found that the 2+1 level has a positive quadrupole moment, which may be interpreted as a soft triaxial deformation. [ABSTRACT FROM AUTHOR]

High-spin states of the stable 157Gd nucleus were studied by a γ–γ coincidence measurement using multiple Coulomb excitation with a 136Xe beam. Two rotational bands of the opposite parity coexisting along the yrast line were extended up to 29/2− and 29/2+, respectively, one of which was of a νh9/2 configuration and the other was of a νi13/2 configuration. Fifteen E1 transitions from the νh9/2 band to the νi13/2 band were observed. Absolute reduced transition probabilities, B(E1), of these transitions were derived from the branching ratios obtained in this experiment and the lifetimes measured in our previous experiment. The B(E1) values ranged between 0.36×10−4 and 5.2×10−4 [e2fm2]. This enhancement could be explained by introducing a parameter which effectively takes into account the octupole softness. It was also found that the matrix elements of the E1 transitions had a term proportional to If(If+1)−Ii(Ii+1) understood in terms of Coriolis mixing. [Copyright &y& Elsevier]

The nucleus 98Mo was multiply Coulomb excited using 20Ne, 84Kr and 136Xe beams. Eighteen E2 and M1 reduced matrix elements connecting 7 low-lying levels have been determined using the least-squares code GOSIA. The results are compared with the predictions of an extended version of the IBM1 model. The quadrupole sum rules approach was used to determine the shape parameters in two 0+ (ground and first excited) states. The rotational invariants Q2 and (cos3δ) obtained show the shape coexistence in 98Mo nucleus: the triaxial ground state and the prolate first excited state. [Copyright &y& Elsevier]

A 84Kr beam was Coulomb-excited on a 98Mo target and a natTa target. Six reduced matrix elements for 5 low-lying states were derived from the analysis using the least-squares code GOSIA. The quadrupole moment of the 21+ was newly obtained. The measured quadrupole moment and the B(E2) values are consistent with large-scale shell-model calculations which give a systematic description of N=50 isotones. [Copyright &y& Elsevier]

For Coulomb excitation experiments using a γ-ray detector array, a position-sensitive particle detector system that has a good angular resolution, capability of managing a high-counting rate, robustness for a radiation damage, compactness (under 110 mm &fgr;) and easiness of handling is necessary. For this purpose we developed a new device utilizing plastic and yttrium aluminum perovskite activated by cerium (formula YAlO[sub 3]:Ce abbreviated YAP Ce) scintillators and a position-sensitive photomultiplier tube. The detector system could operate at a high-counting rate (about 10[sup 5]), and with a good position resolution of 0.5–1.2 mm, which was enough for Doppler correction of the γ rays. It could sustain the radiation damage caused by Coulomb excitation experiments with heavy ions for more than 50 days. The detector chamber was well fitted in the 110 mm &fgr; diameter of the internal space of a compact γ-ray detector array, GEMINI. This was much easier to handle than the position-sensitive gas counter. In Coulomb excitation experiment utilizing this device, the nucleus [sup 74]Ge has been Coulomb excited using a Pb target. The transitional E2 matrix elements have been determined and the device has turned out to be useful in Coulomb excitation experiments with heavy-ion beams. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The level structure of the doubly odd nucleus 146Tb has been studied via the 118Sn(32S, lp3n) reaction using techniques of in-beam γ -ray spectroscopy. Measurements of γ-ray anisotropies, X-γ and γ-γ-t coincidences were performed with 12 BGO(AC)FIPGe detectors. Based on the measured results, the level scheme of 146Tb has been revised significantly and extended up to an excitation energy of 8.39 MeV. The level structure has been interpreted qualitatively by coupling an h11/2 proton-particle and an h11/2 neutron-hole to the excited states in the 146Gd core. [ABSTRACT FROM AUTHOR]

This study investigated intermediate-spin states of 92Zr via the inverse reaction 9Be(86Kr,3n) 92Zr. Seven transitions were newly observed, and a lifetime was extracted for the 10+1 state by analysis of Doppler-broadened line shapes of decay γ rays. A large B(E2) value was obtained for the transition from 10+1 to 8+1, and the magnitude was comparable to that for the deformed excited configurations in 94Zr that have recently been established. A possible origin for such collectivity is discussed qualitatively based on a phenomenological deformed rotor model. Moreover, a multipletlike structure that fits into the systematics for N = 52 even- A isotones is revealed for the negative-parity yrast states. [ABSTRACT FROM AUTHOR]

Corrections to article "High-spin states in 188Au: Further evidence for nonaxial shape," by Y. D. Fang and colleagues that was published in the 2010 issue are presented.