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New transitions in neutron-rich Y100 have been identified in a Be9+U238 experiment with mass and Z gates to provide full fragment identification. These transitions and high spin levels of Y100 have been investigated by analyzing the high statistics γ-γ-γ and γ-γ-γ-γ coincidence data from the spontaneous fission of Cf252 at the Gammasphere detector array. Two new bands, 14 new levels, and 23 new transitions have been identified. The Kπ=4+ new band decaying to a 1s isomeric state is assigned to be the high-K Gallagher-Moszkowski (GM) partner of the known Kπ=1+ band, with the π5/2[522] - ν3/2[411] configuration. This 4+ band is also proposed to be the pseudospin partner of the new Kπ=5+ band with a 5+π5/2[422] - ν5/2[413] configuration, to form a π5/2[422] - ν[3125/2,3/2] neutron pseudospin doublet. Constrained triaxial covariant density-functional theory and quantal particle rotor model calculations have been applied to interpret the band structure and available electromagnetic transition probabilities and are found to be in good agreement with experimental values.

New transitions in neutron rich $^{100}$Y have been identified in a $^9$Be+$^{238}$U experiment with mass- and Z- gates to provide full fragment identification. These transitions and high spin levels of $^{100}$Y have been investigated by analyzing the high statistics $\gamma$-$\gamma$-$\gamma$ and $\gamma$-$\gamma$-$\gamma$-$\gamma$ coincidence data from the spontaneous fission of $^{252}$Cf at the Gammasphere detector array. Two new bands, 14 new levels and 23 new transitions have been identified. The $K^{\pi}=4^+$ new band decaying to an 1s isomeric state is assigned to be the high-$K$ Gallagher-Moszkowski (GM) partner of the known $K^{\pi}=1^+$ band, with the $\pi 5/2[522] \otimes \nu 3/2[411]$ configuration. This 4$^+$ band is also proposed to be the pseudo spin partner of the new $K^{\pi}=5^+$ band with a 5$^{+}$ $\pi 5/2[422] \otimes \nu 5/2[413]$ configuration, to form a $\pi 5/2[422] \otimes \nu [312$ $5/2,3/2]$ neutron pseudospin doublet. Constrained triaxial covariant density functional theory and quantal particle rotor model calculations have been applied to interpret the band structure and available electromagnetic transition probabilities and are found in good agreement with experimental values.

High spin band structures of neutron-rich $^{152--158}\mathrm{Pm}$ isotopes have been obtained from the measurement of prompt $\ensuremath{\gamma}$ rays of isotopically identified fragments produced in fission of $^{238}\mathrm{U}+^{9}\mathrm{Be}$ and detected using the VAMOS++ magnetic spectrometer and EXOGAM segmented Clover array at GANIL and also from the high statistics $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ and $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ data from the spontaneous fission of $^{252}\mathrm{Cf}$ using Gammasphere. The excited states in $^{157}\mathrm{Pm}$ and those above the isomers in even-$A$ Pm isotopes $^{152,154,156,158}\mathrm{Pm}$ have been identified for the first time. The spectroscopic information on the rotational band structures in odd-$A$ Pm isotopes has been extended considerably to higher spins and the possibility of the presence of reflection asymmetric shapes is explored. The configuration assignments are based on the results of cranked relativistic Hartree-Bogoliubov calculations. From the systematics of bands in odd-$A$ Pm isotopes and weak population of opposite parity bands, octupole deformed shapes in neutron-rich Pm isotopes beyond $N=90$ seem unlikely to be present.

The paper reviews the systematic studies of triaxial deformations, new mode excitations and shape evolutions with regard to triaxial deformation in the neutron-rich nuclei with Z = 41-46, A~100-116.

High-spin-level schemes of $^{118,119}\mathrm{Ag}$ are established for the first time by analyzing the high statistics $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ and $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ coincidence data from the spontaneous fission of $^{252}\mathrm{Cf}$ at Gammasphere. Two bands with 12 new levels in $^{118}\mathrm{Ag}$ and three bands with 14 new levels in $^{119}\mathrm{Ag}$ have been identified. A total Routhian surface calculation and projected shell model calculation have been performed to understand the behavior of these two nuclei. The calculations indicate oblate shape in $^{118,119}\mathrm{Ag}$.

An electric power system is monitored and controlled on the basis of its phasor information, such as amplitude, phase angle, and frequency. This phasor can be measured through discrete Fourier transform (DFT) coefficients of its positive nominal frequency. Then, the frequency estimate can be calculated from time variation of the measured phasor angle. The accuracy of the phasor-angle measurement and the frequency estimation are severely affected by noise in the power system signal and the leakage of the negative fundamental frequency in DFT. This paper proposes a DFT-based phasor-angle measurement algorithm to cope with both the noise effect and the leakage effect. In addition, a frequency estimation algorithm is developed to use the same technique in the phasor-angle measurement algorithm. These algorithms introduce two digital filters for the reduction of the noise effect. The effectiveness of the proposed algorithm in the noise effect reduction is verified through simulations.

New level schemes of 112,114,115,116,117,118Pd are established by means of γ – γ – γ , γ – γ – γ – γ and γ – γ ( θ ) measurements of prompt fission γ rays from 252Cf using the Gammasphere multi-detector array. Spins/parities were assigned to levels based on γ – γ angular correlation measurements, level systematics and decay patterns. In the even-N isotopes 112,114,116Pd, two sets of odd-parity bands were identified and extended with spins measured in each band. The odd-parity bands with large level staggerings were interpreted as disturbed chirality with less pronounced triaxial deformations in the Pd isotopes than observed in the chiral symmetry breaking 110,112Ru with maximum triaxiality. Onset of wobbling motion was identified from the sign of the signature splitting in the γ band of even–even 114Pd, and probably also in 116Pd, as first seen in the N = 68 isotone 112Ru. Maximal triaxiality in Ru and Pd isotopes is found to be reached for N = 68 , 112Ru and 114Pd, 4 neutrons more than predicted in the theoretical calculations. The new data and TRS calculations allowed a systematic study of the band crossings in the even-N 112,114,116Pd and odd-N 115,117Pd isotopes. Now we find a new overall, more complex shape evolution than previously proposed from triaxial prolate in 110Pd via triaxial oblate in 112Pd to nearly oblate in 114,116Pd with a large change of the triaxial deformation parameter γ toward nearly oblate in the ( π g 9 / 2 ) 2 alignment in 114,115,116,117,118Pd, and triaxial-prolate–triaxial-oblate shape coexisting bands in 115Pd.

Decays of neutron-rich nuclei $^{82,83}\mathrm{Zn}$ and $^{82,83}\mathrm{Ga}$ produced in proton-induced fission of $^{238}\mathrm{U}$ were studied at the Holifield Radioactive Ion Beam Facility using on-line mass separation and $\ensuremath{\beta}\text{\ensuremath{-}}\ensuremath{\gamma}$ spectroscopy techniques. New $\ensuremath{\gamma}$-ray transitions were identified and level schemes, which include states at high excitation energies in the range between 3--7 MeV were constructed. These high-energy levels were identified to be populated through allowed Gamow-Teller $\ensuremath{\beta}$ transitions, and their structure was interpreted with new shell-model calculations. A $\ensuremath{\beta}$-delayed neutron branching ratio of $69\ifmmode\pm\else\textpm\fi{}7%$ was deduced for $^{82}\mathrm{Zn}$ and revised $\ensuremath{\beta}$-decay half-life values of $^{82}\mathrm{Zn}$ [155(17)(20) ms] and $^{83}\mathrm{Zn}$ [122(28) ms] were determined.

High-spin level schemes of 117,118,119,120,122 Cd are expanded by analyzing our high-statistics triple- and higher-fold coincidence events of prompt fission γ rays from 252 Cf at Gammasphere. Spin/parity assignments were made based on new γ – γ angular correlation measurements and level systematics in the neighboring isotopes. Stretch-aligned band structures observed in low-lying levels in 117,119,121 Cd are seen to weaken with increasing spins, with a quasi-rotational degree of freedom manifested at higher spins. The 5 − levels in even- N 118,120 Cd were tentatively interpreted as candidates of quadrupole–octupole (QOC) coupling. The model-independent spin versus ℏω curves for even- N and odd- N Cd isotopes imply quasi-rotational alignment of an h 11 / 2 neutron pair in the even- N Cd isotopes. The relative energies of the lowest 11 / 2 − , 9 / 2 − , 7 / 2 − , and 15 / 2 − levels in 117 Cd and 119 Cd suggest triaxial shapes based on Meyer-Ter-Vehn theory for these odd- N Cd nuclei. For the even- N Cd isotopes evidence of triaxiality may also be provided by the Shell Correction version of the Tilted Axis Cranking model (SCTAC).

New transitions in neutron rich [Formula: see text]Y have been identified by analyzing the high statistics [Formula: see text]-[Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] coincidence data from the spontaneous fission of [Formula: see text]Cf at the Gammasphere detector array. Shell model calculations were performed and are found in good agreement with experimental data. The ground state is nearly spherical but a new excited band has large deformation.

Collective bands in the neutron-rich 103 Nb nucleus have been investigated by measuring prompt γ -rays following spontaneous fission of 252 Cf. Three new bands have been identified. The band based on the 716.8 keV level is proposed as a candidate for the K π = 9 / 2 + one-phonon γ -vibrational band, and the band built on the 1282.1 keV level is proposed as a candidate for the K π = 13 / 2 + two-phonon γ -vibrational band. The two-phonon γ -vibrational band is the first such band identified in odd- Z nuclei.

Rotational bands in 108,110,112Ru have been investigated by means of γ – γ – γ and γ – γ ( θ ) coincidences of prompt γ rays emitted in the spontaneous fission of 252Cf. The positive parity bands are described by different versions of IBA, where 108Ru is best described as a γ-soft nucleus whereas 110,112Ru are more like rigid triaxial rotors. New Δ I = 1 negative parity doublet bands are found. In case of 110,112Ru, these are interpreted as soft chiral vibrations. Many of the experimental findings can be explained by microscopic calculations that combine the TAC mean-field with random phase approximation but a simple geometrical explanation is not apparent.

The previously reported levels assigned to 151,152,153Pr have recently been called into question regarding their mass assignment. The above questioned level assignments are clarified by measuring g-transitions tagged with A and Z in an in-beam experiment in addition to the measurements from 252Cf spontaneous fission (SF) and establish new spectroscopic information from $N=84$ to $N=94$ in the Pr isotopic chain. The isotopic chain 143-153Pr has been studied from the spontaneous fission of 252Cf by using Gammasphere and also from the measurement of the prompt g-rays in coincidence with isotopically-identified fission fragments using VAMOS++ and EXOGAM at GANIL. The latter were produced using 238U beams on a 9Be target at energies around the Coulomb barrier. The g-g-g-g data from 252Cf (SF) and those from the GANIL in-beam A- and Z-gated spectra were combined to unambiguously assign the various transitions and levels in 151,152,153Pr and other isotopes. New transitions and bands in 145,147,148,149,150Pr were identified by using g-g-g and g-g-g-g coincidences and A and Z gated g-g spectra. The transitions and levels previously assigned to 151,153Pr have been confirmed by the (A,Z) gated spectra. The transitions previously assigned to 152Pr are now assigned to 151Pr on the basis of the (A,Z) gated spectra. Two new bands with 20 new transitions in 152Pr and one new band with 7 new transitions in 153Pr are identified from the g-g-g-g coincidence spectra and the (A,Z) gated spectrum. In addition, new g-rays are also reported in 143-146Pr. New levels of 145,147-153Pr have been established, reliable mass assignments of the levels in 151,152,153Pr have been reported and new transitions have been identified in 143-146Pr showing the new avenues that are opened by combining the two experimental approaches.

New level schemes of odd-Z 99,101Y (Z = 39) and 101,105Nb (Z = 41) are established based on the measurement of prompt gamma rays from the fission of 252Cf at Gammasphere. Bands of π5/2+[422], π5/2−[303] and π3/2−[301] are observed and extended to provide spectroscopic information concerning nuclear shapes in this important odd-Z region. In combination with the level structure of the odd-Z Tc (Z = 43), Rh (Z = 45) and the neighbouring even-Z isotopes the level systematics, signature splittings and kinematic and dynamic moments of inertia of the bands in the Y and Nb isotopes are discussed in terms of shape transition and triaxiality. The pronounced difference observed in the signature splittings between Y and Tc, Rh isotopes is interpreted as evidence of the axially symmetric deformed shape in the Y isotopes, and, as previously reported, large and near maximum triaxiality in Tc–Rh isotopes. The likely lowering of crossing frequencies of the ground-state bands in Tc and Rh isotones in comparison with those in Y isotones also implies a shape transition from axially symmetric deformed shapes in Y nuclei to triaxiality in Tc and Rh isotones. Triaxial-rotor-plus-particle model calculations strongly support a pure axially symmetric shape with large quadrupole deformation in Y isotopes. The model calculations yielded γ values ranging from −19° to −13° for the 5/2+[422] ground-state bands of 101,103,105Nb and of −5° for the two negative-parity bands in 101Nb. The fact that Nb isotopes have intermediate values of signature splitting and band crossing frequencies between those of Y and Tc, Rh isotopes is interpreted as that the Nb isotopes are transitional nuclei with regard to triaxial deformation. A correlation of quadrupole deformations and of triaxiality is seen in the neutron-rich nuclei with Z = 39–45.

The structure of magic neutron-rich nickel isotopes produced in the fragmentation of a 140 A MeV 86 Kr beam was investigated. For the first time four gamma transitions were assigned to the decay of the I π = 8 + , T 1 / 2 = 590 −110 +180 ns isomer, thus establishing the 0 + – 2 + – 4 + – 6 + – 8 + ground-state band in 76 Ni. The previously unknown 2 + and 4 + levels belonging to the ground-state band in 74 Ni were identified in the β decay of 74 Co ( T 1 / 2 = 30 ( 3 ) ms ) . The decay properties of 72 Co → 72 Ni were verified and confirmed on the basis of γ – γ coincidence data. The relevance of the measured level properties for the magicity of 78 Ni is analyzed with the help of advanced shell-model predictions.

From multiparameter data obtained at Lawrence Berkeley National Laboratory, the integral characteristics of the prompt γ-ray emission were extracted for tripartition of 252Cf with He, Be and C being the third light charged particle. We used multifold γ-ray coincidence spectra for the determination of γ-ray multiplicities assuming a Gaussian distribution for γ-ray multiplicity. The multiplicity distribution characteristics, i.e. mean multiplicity and its dispersion were obtained by minimizing with respect to the calculated values of probabilities of multifold γ-ray coincidences using a combinatoric method. Comparison with the known experimental data from binary fission was made. Further, we investigated dependencies of the mean γ-ray multiplicity on the kinetic energy of the light charged particle. The mean γ-ray multiplicity for He ternary fission is found to increase rapidly with increasing kinetic energy of He in the region less than 11 MeV and then decrease slowly with increasing kinetic energy of He. The anomalous behaviour of γ-ray emission is discussed. The mean γ-ray multiplicity was determined for the first time for Be and C ternary fission. For Be, the γ-ray multiplicity as a function of kinetic energy was obtained as well.

New excited states built on the 11/2− isomeric states are identified in neutron-rich 121,123Cd, respectively, with gammasphere by measuring three-and higher-fold prompt coincidences following the spontaneous fission of 252Cf. The new data suggests that the 11/2− isomers in the odd-A Cd isotopes with N ≥ 75 have spherical shape similar to those in Te. It is suggested that the backbending observed at ω ≈ 0.445 MeV in 121Cd is because of the alignment of the h11/2 neutron pair.

High spin states in neutron-rich $^{147}\mathrm{Ce}$ have been reinvestigated by measuring the triple- and fourfold $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence data observed in the spontaneous fission of $^{252}\mathrm{Cf}$. The positive-parity band is expanded to spin (45/2) $\ensuremath{\hbar}$ and the negative-parity side band is expanded to spin (39/2) with a new third band connected to it. An octupole band structure with $s=+i$ was proposed. The systematic characteristics of the octupole correlations have been discussed. Reflection asymmetric shell model calculations for the octupole band structure of $^{147}\mathrm{Ce}$ are in good agreement with the experimental data.

The levels in 162Gd were identified in spontaneous fission studies. Its transition energies are remarkably similar to those in 160Gd. From that work, an analysis of yrast bands in even-even proton to neutron-rich Ba to Pb nuclei led to the discovery of a new phenomenon, shifted identical bands (SIB). SIBs are yrast bands in neighboring nuclei (a, b) with moments of inertia which are identical when shifted by a constant amount ?, so J 1a (1+?)=J 1b , from 2+ to 8+ and higher to 16+. Out of over 700 comparisons, 55 SIBs were found from stable to the most neutron-rich Ce-W nuclei with $$\left| {\bar k} \right|$$ between 1.5% and 13%, where the spread in ? is less than 1%, and only four identical bands ( $$\bar k \cong 0$$ ). As examples, we found for 158Sm-160Gd, $$\bar k = \left( { - 3.2_{ - 0.2}^{ + 0.1} } \right)\%$$ (where the is the total spread in ? from -3.1 to -3.4); 156Nd-160Gd, (-10.6 -0.2 +0.4 )%; 158Sm-160Sm, (3.4 -0.3 +0.5 )%. The J 1 values were fitted to a variable moment of inertia model with parameters J 0 and C whose values correlate with the SIB J 1 values. The SIBs are not correlated either with deformation or with the N p N n product of the IBA model.

A new interpretation for the two new rotational bands in the 102Nb nucleus is presented. These two bands in 102Nb are proposed to be semi-decoupled bands where the odd proton with Ωp = ½ is coupled to the rotation axis and odd neutron with Ωn≠½ is strongly coupled to the deformation axis of the 100Zr deformed core. The likely orbitals are π½[431] and ν3/2[532].

Short lived neutron rich nuclei including 93 Br, 93 Kr and 94 Kr were produced in proton induced fission of 238 U at the HRIBF in Oak Ridge. Their beta decay was studied by means of a high resolution on line mass separator and beta gamma spectroscopy methods. The half life of 93Br T1/2 = 152(8) ms and delayed branching ratio of Pn = 53-8+11 may be compared to the previously reported values of T1/2 = 102(10) ms and Pn = 68(7)%. At the same time the half life of 94Kr T1/2 = 227(14) ms and B delayed branching ratio of Pn = 1.9+0.6 0.2 % of 93Kr are in very good agreement with literature values. The decay properties of 93Br include four new gamma transitions following beta delayed neutron emission.

High spin levels of the very neutron-rich ${}^{152}$Ce have been investigated by measuring the prompt $\ensuremath{\gamma}$ rays in the spontaneous fission of ${}^{252}$Cf. The yrast band is confirmed and a new side-band has been identified. The side-band is tentatively assigned with negative parity and an octupole band structure with $s=+1$ in ${}^{152}$Ce has been proposed. Based on the theoretical calculations and systematic comparisons, the characteristics of the octupole correlations have been discussed.

New information is reported on single-neutron states above the doubly closed-shell nucleus 132Sn. A radioactive ion beam of 134Te(N = 82) at 565 MeV and a stable ion beam of 136Xe(N = 82) at 560 MeV were used to study single-neutron states in the N = 83 nuclei 135Te and 137Xe, respectively, by (13C, 12C ) and (9Be, Be ) direct reactions in inverse kinematics. Particle- and particle- - coincidence measurements using HPGe and CsI arrays allowed determination of decay paths, high-precision level energies, multipolarities of transitions, and relative cross sections. One-neutron transfer with heavy ions is employed to gain selectivity to both low- and high-spin single-neutron states above the N = 82 shell closure. Results are presented for the 13/2+ states in the N = 83 nuclei 135Te and 137Xe at 2108.8(9) keV and 1752.6(3) keV, respectively, and for the 3 collective octupole state observed at 3749(5) keV in 134Te(N = 82) inelastic scattering, all previously unknown. While the 13/2+ state (or 1i13/2 centroid) in 133Sn(Z = 50, N = 83) remains unknown, the present results provide the best empirical measure of its energy available to date.

The {beta} decays of neutron-rich nuclei near the doubly magic {sup 78}Ni were studied at the Holifield Radioactive Ion Beam Facility using an electromagnetic isobar separator. The half-lives of {sup 82}Zn (228 {+-} 10 ms), {sup 83}Zn (117 {+-} 20 ms), and {sup 85}Ga (93 {+-} 7 ms) were determined for the first time. These half-lives were found to be very different from the predictions of the global model used in astrophysical simulations. A new calculation was developed using the density functional model, which properly reproduced the new experimental values. The robustness of the new model in the {sup 78}Ni region allowed us to extrapolate data for more neutron-rich isotopes. The revised analysis of the rapid neutron capture process in low entropy environments with our new set of measured and calculated half-lives shows a significant redistribution of predicted isobaric abundances strengthening the yield of A > 140 nuclei.

Excited states of neutron-rich nucleus {sup 82}Ge were studied from the spontaneous fission of {sup 252}Cf. Eleven new transitions and seven new levels in {sup 82}Ge were identified by using X(Dy)-{gamma}-{gamma} and {gamma}-{gamma}-{gamma} triple coincidences. Possible excited deformed rotational bands are observed, for the first time, in this nuclear region. Coexistence of the spherical ground and deformed excited shapes is proposed in {sup 82}Ge. These deformed rotational bands can be formed by two-particle, two-hole excitations with the 0{sup +} pairing energy states of the {nu}9/2[404]{sup -2} x 1/2[431]{sup 2} configuration across the N=50 closed shell.

High-spin excited states in the neutron-rich nucleus $^{115}\mathrm{Rh}$ have been identified for the first time by studying prompt $\ensuremath{\gamma}$ rays from the spontaneous fission of $^{252}\mathrm{Cf}$ with the Gammasphere detector array. A new yrast band and a sideband are built in $^{115}\mathrm{Rh}$. This level scheme is proposed to be built on the $7/{2}^{+}$ ground state. The existence of a large signature splitting and an yrare band in $^{115}\mathrm{Rh}$ shows typical features of a triaxially deformed nucleus. The rigid triaxial rotor plus particle model is used to interpret the level structure of $^{115}\mathrm{Rh}$. The level energies, the $\ensuremath{\gamma}$ branching ratios, the large signature splitting in the yrast band, and the inverted signature splitting in the yrare band in $^{115}\mathrm{Rh}$ are reproduced very well. Strong $K$ mixing occurs in $^{115}\mathrm{Rh}$ at high spin.

High-spin excited states in the very neutron-rich nucleus $^{114}\mathrm{Rh}$ have been studied by examining the prompt $\ensuremath{\gamma}$ rays emitted in the spontaneous fission of $^{252}\mathrm{Cf}$ with the Gammasphere detector array. A high-spin level scheme of $^{114}\mathrm{Rh}$ has been established for the first time with 13 new levels. The level scheme is proposed to be built on a ${7}^{\ensuremath{-}}$ state. The existence of a relatively large signature splitting and an yrare band show features which may indicate triaxial deformation. The phenomenon of signature inversion has been observed in $^{114}\mathrm{Rh}$ at $I=12 \ensuremath{\hbar}$. The observed signature inversion of $^{114}\mathrm{Rh}$ is interpreted successfully in terms of the triaxial projected shell model. Theoretical calculations suggest that the negative-parity, yrast band of $^{114}\mathrm{Rh}$ has the two-quasi-particle configuration of $\ensuremath{\pi}{g}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{h}_{11/2}$, consistent with the systematics of odd-odd Rh isotopes. The signature inversion at spin $12 \ensuremath{\hbar}$ may be attributed to the change of rotational mode, from quasi-particle aligned rotation at low spins to collective rotation at high spins.

High-spin levels of the neutron-rich $^{114}\mathrm{Ru}$ have been investigated by measuring the prompt $\ensuremath{\gamma}$ rays in the spontaneous fission of $^{252}\mathrm{Cf}$. The ground-state band and one-phonon $\ensuremath{\gamma}$-vibrational band have been extended up to 14${}^{+}$ and 9${}^{+}$, respectively. Two levels are proposed as the members of a two-phonon $\ensuremath{\gamma}$-vibrational band. A back bending (band crossing) has been observed in the ground-state band at $\ensuremath{\hbar}\ensuremath{\omega}\ensuremath{\approx}$ 0.40 MeV. Using the triaxial deformation parameters, the cranked shell model calculations indicate that this back bending in $^{114}\mathrm{Ru}$ should originate from the alignment of a pair of ${h}_{11/2}$ neutrons. Triaxial projected shell model calculations for the $\ensuremath{\gamma}$-vibrational band structures of $^{114}\mathrm{Ru}$ 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.

NF-κB has been implicated as a therapeutic target for the treatment of rheumatoid arthritis. We previously synthesized a thiourea analogue, SPA0355, which suppressed NF-κB activity. Here we have assessed the anti-inflammatory and anti-arthritic effects of SPA0355.We evaluated the effects of SPA0355 on human rheumatoid fibroblast-like synoviocytes in vitro and on collagen-induced arthritis (CIA) in mice in vivo.In vitro experiments demonstrated that SPA0355 suppressed chemokine production, matrix metalloproteinase secretion and cell proliferation induced by TNF-α in rheumatoid fibroblast-like synoviocytes. In addition, SPA0355 inhibited osteoclast differentiation induced by macrophage colony-stimulating factor and the receptor activator of NF-κB ligand, in bone marrow macrophages. Mice with CIA that were pretreated with SPA0355 had a lower cumulative disease incidence and severity of arthritis, based on hind paw thickness, radiological and histopathological findings, and inflammatory cytokine levels, than mice treated with vehicle. Mice treated with SPA0355, after the onset of CIA, also showed significantly decreased disease incidence and joint oedema. The in vitro and in vivo protective effects of SPA0355 were mediated by inhibition of the NF-κB signalling pathway.Taken together, these results suggested that using SPA0355 to block the NF-κB pathway in rheumatoid joints reduced both the inflammatory responses and tissue destruction. Therefore, SPA0355 may have therapeutic value in preventing or delaying joint destruction in patients with rheumatoid arthritis.

Triple coincidences between prompt γ-rays emitted in the spontaneous fission of 252Cf were measured with Gammasphere. These data are used to measure the angular correlation of cascades of γ-rays from excited states of neutron rich fission fragments stopped in an unmagnetized iron foil. The hyperfine fields in the iron lattice cause attenuations of the angular correlations between γ-rays emitted from the excited states which have sufficiently long lifetimes. This attenuation is measured and used to calculate the g-factors of excited states in many neutron rich nuclei. © 2007 Elsevier B.V. All rights reserved.

High spin states of neutron-rich nuclei such as 133,134Te, 93Sr, 105Nb have been studied by measuring γ- γ- γ coincidences (cube), γ- γ- γ- γ coincidences (hypercube) and angular correlations from the spontaneous fission of 252Cf with the LBNL Gammasphere detector array. Four types of particle-hole bands built on the known 334.3 keV isomer in 133Te were identified. The level structure of 93Sr is interpreted, in part, as arising from the weak coupling of the 1d5/2 neutron hole to the yrast states of the 94Sr core. The g-factor of the 4+ state in 134Te was measured, for the first time, by using a new technique developed for measuring angular correlations with Gammasphere. A new level scheme of 105Nb was established. Three new collective bands were identified with a total of 14 new levels and 36 new γ transitions. In 117-122Cd, a shift to more slightly deformed structures was found where the excited levels do not fit the long held picture of one, two and three phonon bands.

The structure of Tc nuclei is extended to the moreneutron-rich regions based on measurements of prompt gamma rays from thespontaneous fission of 252Cf at Gammasphere. The level scheme of N=67neutron-rich (Z=43) 110Tc is established for the first time and that of111Tc is expanded. The ground-state band of 111Tc reaches theband-crossing region and the new observation of the weakly populatedalpha = -1/2 member of the band provides important information ofsignature splitting. The systematics of band crossings in the isotopicand isotonic chains and a CSM calculation suggest that the band crossingof the gs band of 111Tc is due to alignment of a pair of h11/2 neutrons.The best fit to signature splitting, branching ratios, and excitations ofthe ground-state band of 111Tc by RTRP model calculations result in ashape of epsilon2 = 0.32 and gamma = -26 deg. for this nucleus. Itstriaxiality is larger than that of 107Tc, to indicate increasingtriaxiality with increasing neutron number. The identification of theweakly-populated "K+2 satellite" band provides strong evidence for thelarge triaxiality of 111Tc. In 110Tc the four lowest-lying levelsobserved are very similar to those in 108Tc. At an excitation of 478.9keV above the lowest state observed, ten states of a delta I = 1 band areobserved. Thismore » band is very analogous to the delta I = 1 bands in106,108Tc, but it has greater signature splitting at higherspins.« less

From prompt γ-γ-γ coincidence studies with a 252Cf source, the yrast levels were identified from 2+ to 16+ and 14+ in neutron-rich 162,164Gd, respectively. Transition energies between the same spin states are higher and moments of inertia lower at every level in N = 100 164Gd than in N = 98 162Gd. These observations are in contrast to the continuous decrease in the 2+ energy to a minimum at neutron midshell (N = 104) in Er, Yb, and Hf nuclei.