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Background: Investigation of the $_{62}^{140}\mathrm{Sm}_{78}$ nucleus, situated in the area close to the magic $N=82$ neutron shell, offers the opportunity to find and study interesting phenomena resulting from the interplay of collective and other degrees of freedom.Purpose: Experimental identification of low-spin low-energy levels, particularly ${0}^{+}$, in $^{140}\mathrm{Sm}$ and theoretical interpretation within the collective general Bohr Hamiltonian (GBH) model.Method: The $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ angular correlation technique for $\ensuremath{\gamma}$ radiation after the $\ensuremath{\beta}$/EC decay of $^{140}\mathrm{Eu}\ensuremath{\rightarrow}^{140}\mathrm{Sm}$ and $^{140}\mathrm{Gd}\ensuremath{\rightarrow}^{140}\mathrm{Eu}\ensuremath{\rightarrow}^{140}\mathrm{Sm}$ was used to determine spins of excited states of $^{140}\mathrm{Sm}$. The $^{140}\mathrm{Gd}$ and $^{140}\mathrm{Eu}$ nuclei were produced in the $^{104}\mathrm{Pd}+^{40}\mathrm{Ar}$ reaction at the HIL UW cyclotron. In the theoretical part the full five-dimensional GBH model was applied in two variants: the simple phenomenological Warsaw model and the microscopic version with six inertial functions and a potential calculated from mean-field theory.Results: The spin and parity of six low spin (0,1,2) low lying excited levels of $^{140}\mathrm{Sm}$ were measured. Two new states at around 2 MeV were identified. A analysis of the consequences of possible admixtures on the determination of the spin of a level was performed. The theoretical models applied successfully describe most of the spectrum of $^{140}\mathrm{Sm}$ giving hints on the origin of the states observed in the experiment.Conclusions: Significant softness against nonaxial deformation seems to be essential to interpret the properties of $^{140}\mathrm{Sm}$. Further experimental studies are needed to check if some low-energy excitations are not deformation driven.

Background: The γ softness of 136Nd makes it possible to study the shape changes induced by two-proton or two-neutron excitation. Purpose: We measure the lifetimes of two-quasiparticle states of the bands based on the 10+ states at 3296 and 3279 keV to investigate the shape change induced by the alignment of two protons or two neutrons in the h11/2 orbital. Methods: The recoil-distance Doppler shift method was used for the study of 136Nd studies, which was formed by the fusion reaction 120Sn(20Ne, 4n)136Nd, at Ebeam = 85 MeV. Calculations were performed within the microscopic-macroscopic approach, based on the deformed Woods-Saxon single-particle potential and the Yukawa-plus-exponential macroscopic energy. Results: The lifetime of the 10+ state at 3279 keV of 136Nd was measured to be T 10+1/2 = 1.63(9) ns. The lifetimes of the 2+ state at 374 keV and of the 12+ state at 3686 keV of the ground band were also measured to be T 2+1/2 = 26.5(14) ps and T 12+1/2 = 22.5(14) ps. Conclusions: The measured lifetime of 10+ the state at 3279 keV together with other observables confirm the structure change in 136Nd. A rather small reduced hindrance of the electromagnetic decay of the 10+ state at 3279 keV would be consistent with its K-mixed character.

The $g$ factor of the 56 ns half-life isomeric state in $^{128}\mathrm{Cs}$ has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). $g$-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured $g$ factor $g=+0.59(1)$ shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in $^{128}\mathrm{Cs}$ demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.

A semi-thick target method has been used to measure the stopping power for recoils produced in the 120 Sn( 14 N, 5n) 129 La, 120 Sn( 11 B, 4n) 127 Cs and 118 Sn( 11 B, 4n) 125 Cs reactions by γ-ray lineshape analysis. The target quality and thickness (1.2 mg/cm 2 ) were determined by the Rutherford backscattering spectrometry technique. Electronic and nuclear stopping-power parameters were determined for Cs and La ions in Sn and compared with parameters measured with the same method for Pm, Sm and Nd ions in Cd and I ions in Ag. A comparison with the LSS theory was made for the energy range below 0.2 MeV/nucleon, where the Bethe–Bloch formula has no application.

The properties of the $K$-isomer decays in the $^{134}\mathrm{Nd}$ and $^{184}\mathrm{Pt}$ nuclei have been investigated. Measurements were carried out in $e\ensuremath{-}\ensuremath{\gamma}$ and $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence modes using electron spectrometers coupled to the central European Array for Gamma Levels Evaluations at the Heavy Ion Laboratory of the University of Warsaw. Internal conversion coefficients were obtained for transitions relevant to the decay of the isomeric states, allowing the determination of multipolarities and mixing ratios as well as hindrance factors. Two possible causes of the weakening of the $K$ forbiddenness, namely rotational $K$ mixing (Coriolis interaction) and triaxiality, are briefly discussed using schematic theoretical models.

The EAGLE array (European Array for Gamma Levels Evaluations) has been designed as a multi-configuration detector set-up for in-beam nuclear spectroscopy studies at the Heavy Ion Laboratory of the University of Warsaw. The array can accommodate a maximum of 30 Compton suppressed Ge detectors coupled to various ancillary devices, such as a 4 π inner ball consisting of 60 BaF2 crystals, 30 element 4 π silicon detector array, compact scattering chamber equipped with 110 PIN diodes placed at backward angles and a conversion-electron spectrometer.

Lifetimes of the yrast levels with spins I π = 23/2− to 39/2− in 129La produced via the 120Sn(14N, 5n) reaction at a beam energy of 77MeV have been measured by the Doppler shift attenuation method. The properties of the studied levels belonging to the πh11/2 band were compared with the theoretical predictions obtained in the framework of the core quasi-particle coupling model. It is suggested that the rigid-rotor model used to describe the cores is too simplified as the even-even nuclei from the A ∼ 130 region are susceptible to shape deformation. Reasonable agreement was obtained with the phenomenological cores based on the experimental data of 128Ba.

Modernization of the 210,000 tpy VAW Rheinwerk smelter includes installation of point feeder, alumina conveying system, state-of-the-art pot control system and foresees an increase in amperage of up to 175 kA. For the modernized pots concepts for the potlining as well as for improvements of the busbar system were developed based solely on computer simulations. For the layout of the potlining a new three-dimensional thermoelectric cell model was applied that allows prediction of side ledge contours as well as heat and voltage balances. Based on this model the choice of semi-graphitic vs. fully graphitized cathode blocks was evaluated with respect of the anticipated increase in system amperage. Temperature fields and side ledge contours predicted are in good agreement with measurements. The busbar system, designed originally for a current load of 110 kA, was improved in a very efficient manner to cope with the higher amperage. Magneto-hydrodynamic simulations predicted and plant measurements demonstrated significant improvements in cell stability and performance.

The 113Ru and 113Rh nuclei, produced in the spontaneous fission of 248Cm and in proton-induced fission of 238U , were studied by means of prompt gamma spectroscopy using the EUROGAM 2 array of Anti-Compton spectrometers and the IGISOL mass separator, respectively. For the 0.5s isomer, found in 113Ru in our recent study we propose the 7/2-[523] configuration. The present data indicate spin and parity 1/2+ for the ground state in 113Ru . This and some new data on the excited levels in 113Rh allows reinterpretation and a better understanding of the β- {} decay scheme of 113Ru . The properties of 113Ru were studied in the frame of the Core-Quasiparticle Coupling model, which has well reproduced the experimental data.

Results of the DSAM lifetime measurements in supposed chiral partner bands of 128 Cs and 132 La are presented. Experimental reduced transition probabilities in 128 Cs are compared with theoretical calculations done in the frame of the Core-QuasiParticle Coupling model. The electromagnetic properties and energy pattern of partner bands show that 128 Cs is the best candidate revealing the chiral symmetry breaking phenomenon.

Lifetimes of yrast levels with spins Iπ = 23/2--43/2- in 131La populated in the 122Sn(14N, 5n) reaction at a beam energy of 70MeV are measured by the Doppler Shift Attenuation method. A model of side-feeding population is presented. The model parameters are determined in an experiment based on the lineshape of γ-transitions from two highest spin levels and from the intensity distribution along the yrast band. The properties of the h11/2 band in 131La are compared with the theoretical predictions obtained in the framework of the Core-Quasi-Particle Coupling and the self-consistent Total Routhian Surface models.

The magnitudes and signs of twenty eight E2 and three M1 matrix elements involving 17 low-lying excited states in 104Ru have been measured by Coulomb excitation using 208Pb, 136Xe and 58Ni ions. The completeness of the set of E2 matrix elements is sufficient to extract, directly from the data, the expectation values of the intrinsic-frame E2 moments that provide considerable insight into the underlying collectivity. The measured E2 properties strongly correlate with macroscopic quadrupole collective degrees of freedom. Detailed comparison of the experimental results and theoretical microscopic calculations within the general quadrupole collective Bohr Hamiltonian are presented. Very good agreement of calculations and experiment is achieved without any parameters fitted to the 104Ru experimental data. Results of phenomenological γ-unstable and γ-rigid models are also given.

The linear polarisation sensitivity of the CLUSTER detector used in the EUROBALL III array was measured. Measurements confirm the results of the Monte Carlo simulation.

Excited states in 110Sn and 111Sn nuclei have been investigated using in-beam γ-ray spectroscopic methods. An 16O beam with an energy of 60-80MeV was used to bombard a 98Mo target. On the basis of the relative excitation functions, γ-ray angular distributions, γ-γ and γ-time distributions, γ-ray multiplicity and total energy data, the level schemes of 110Sn and 111Sn have been studied and extended up to Eexc ∼ 11.5MeV, I = 24ℏ, and Eexc ∼ 11.1MeV and I = (51/2)ℏ, respectively. An extension of the intruder, g.s. and negative-parity bands, as well as 5 new band-like structures are proposed in 110Sn. The nature of newly introduced collective band 8 as well as 10+ states fed in the decay of the collective band is discussed. In the 111Sn nucleus an intruder band based on the 23/2- state has been reinvestigated and the extension of the g.s. band and second negative-parity band is given. Evidence for neutron-core coupling in 111Sn is found. The structure and systematics of excited states in light Sn isotopes is discussed.

The lifetime of levels in 128 Cs and 132 La have been measured in-beam of the Warsaw University Cyclotron using DSA method. The absolute M1 and E2 transition probabilities have been deduced. Two cases have been found: 132 La where the B(E2) values in yrast and partner bands differ up to 30 times and 128 Cs - the B(E2) values in both bands differ only few times. It seems that bands in 128 Cs are better candidates for chiral partner bands than the ones in 132 La .

An even-odd isotope of ruthenium, 111Ru, is investigated in the framework of the Core-Quasiparticle Coupling model. The energy levels and wave functions of low-lying states are calculated. The only one parameter adjusted to obtain the results in agreement with experimental data is the strength of the core-particle quadrupole-quadrupole interaction. The neighbouring even-even cores, 110Ru and 112Ru, are described by means of the collective “quadrupole plus pairing” model with the Bohr Hamiltonian determined fully from a microscopic theory without any adjustable parameter. Results for 111Ru are compared with a new set of experimental data obtained recently. An importance of the pairing interaction is confirmed. A remarkable agreement of theoretical results and experimental data is obtained for all eight positive- and negative-parity bands delivered by the newest experiment.

Lifetimes of the h 11/2 decoupled band in 131 La and supposed chiral bands in odd-odd 132 La have been measured using the Doppler Shift Atenuation method. The properties of all bands have been calculated in terms of the Core Quasi Particle Coupling and Core Particle Hole Coupling models by using in both cases the same phenomenological core of 130 Ba . A new band in 132 La has been found.

The previously accepted spin values of the 991 and 1599 keV levels in $^{140}\mathrm{Sm}$ have been revised and established as $2{}^{+}$ and $0{}^{(+)}$, respectively. The $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ angular correlation method was used to determine the new spin values. The excited low-spin levels in $^{140}\mathrm{Sm}$ were populated in the $^{140}\mathrm{Eu}{\ensuremath{\rightarrow}}^{140}\mathrm{Sm}$ and $^{140}\mathrm{Gd}\ensuremath{\rightarrow} ^{140}\mathrm{Eu}{\ensuremath{\rightarrow}}^{140}\mathrm{Sm}$ decays. The $^{140}\mathrm{Gd}$ and $^{140}\mathrm{Eu}$ nuclei were produced in the $^{112}\mathrm{Cd}+^{32}\mathrm{S}$ reaction at a beam energy of 155 MeV.

Lifetimes of excited states in 118Te have been measured using the Doppler Shift Attenuation (DSA) and Recoil Distance (RD) methods in the 109Ag(13C, p3n) reaction at a beam energy of 54 MeV. Lifetime values of the ground-state band levels with spins I π = 2+-16+ have been obtained. The excitation energies and B(E2) values are interpreted in the framework of a version of IBFM ( IBM + 2qp) with the maximum boson number exceeding its standard value. A satisfactory agreement with experimental level scheme and B(E2) values for the ground-state band is achieved.

High-spin states in 142Gd have been populated by means of the 99Ru(48Ti, 2p3n) reaction at 240 MeV and investigated with the γ-spectrometer EUROBALL III and the charged-particle detector array ISIS. The features of four dipole bands have been determined and compared with tilted-axis cranking model calculations indicating that they are magnetic rotational bands. A transition from regular to irregular bands has been found approaching N = 82 demonstrating that this is a general phenomenon in nuclei near a double-shell closure.

International audience; Electromagnetic transition strengths and spectroscopic quadrupole moments for Sm-140 were measured by means of multi-step Coulomb excitation with radioactive beam at the ISOLDE facility at CERN. A complementary experiment was performed at the Heavy Ion Laboratory in Warsaw to assign spins for non-yrast states using the angular correlation technique. Based on the new experimental data previous spin assignments need to be revised.

The designed and constructed at the University of Lodz an electron spectrometer is devoted to “in-beam” measurements. The apparatus is characterized by high efficiency up to 9%, good energy resolution (FWHM = 5 keV at 482 keV) and, what is very important good suppression of delta electrons, positrons, and photons emitted by the targets. This achievement was obtained using a combination of magnetic field in two different layouts: perpendicular and parallel to the axis of the spectrometer being orthogonal to the beamline. The conversion-electron spectrometer coupled to the EAGLE array was successfully tested in an “in-beam” measurement.

The “quadrupole plus pairing” collective model is constructed for the microscopic description of low-lying collective states of even-even transitional nuclei. Inclusion of the model to the core-quasiparticle coupling model in order to describe odd nuclei is realized. An approximation scheme suitable for investigation of the quadrupole excitations is demonstrated. Exemplary results of microscopic calculations for the Ru isotopes are shown.

Lifetimes in four negative-parity bands of 119 I were measured using DSAM and RDM. 119 I nuclei were produced in the 109 Ag( 13 C,3n) reaction, γγ coincidences were collected using the NORDBALL array. RDDSA — a new method of RDM analysis — is described. This method allowed for the self-calibration of stopping power. From 31 measured lifetimes, 39 values of B (E2) were established. Calculations in the frame of the Core Quasi Particle Coupling (CQPC) model were focused on the problem of susceptibility of the nucleus to γ -deformation. It was established that nonaxial quadrupole deformation of 119 I plays on important role. The Wilets–Jean model of a γ -soft nucleus describes the 119 I nucleus in a more consistent way then the Davydov–Filippov model of a γ -rigid nucleus.

The modified procedure of RDM and DSAM data analysis applied to lifetime measurements in 119I presented. The main points are: the Recoil Distance Doppler Shift Attenuation Method, the evaluation of side-feeding time, and self-calibration of stopping-power parameters by “semi-thick” target method.

A superdeformed band has been discovered in 143Gd consisting of 15 transitions. It does not show the band crossing observed in the neighbouring heavier Gd isotopes and it is degenerate with the superdeformed band in 143Eu. In contrast to other degenerate bands at superdeformed shape, the configurations of the bands are quite different here. They result from the exchange of a ν64 with a π[404]9/2 configuration. In addition, a collective band has been observed which adopts a well-deformed triaxial shape at high spins according to calculations. The transition from highly to superdeformed shapes proceeds via triaxial shapes.

The correlation between linear polarization of one γ-ray quantum and polarization of the next γ-ray quantum emitted in a cascade from an oriented nucleus is discussed. This correlation forms the basis for developing the PPCO method which, in principle, can determine spins, parities and multipolarities. The method is particularly useful when γ rays are produced in heavy ion reactions, ensuring a high spin alignment. The paper presents an experimental test of the PPCO method and the results suggest, that this method can be applied with success in modern γ-ray spectroscopy in which a large number of detectors are sensitive to the polarization (e.g. the CLOVER detectors). When this method is combined with an angular correlation analysis, the number of the possibilities concerning spins, parities and multipolarity sequences can be reduced significantly.

The study of the polarization direction correlation method (PDCO) for γ quanta emitted from the nuclear states oriented in fusion-evaporation reactions is discussed with emphasis on making unique multipolarity assignments. The method is applied to the data coming from a typical experiment performed with the EUROGAM II array, where polarization-sensitive CLOVER detectors were used. The accuracy obtained in the experiment for the studied transitions was high enough to exclude, using the PDCO method, most of the ambiguities which occur if the assignments are made on the basis of angular correlation measurements alone.

High-spin states in the odd-$A{ }^{113}\mathrm{Sn}$ nucleus have been investigated with the ${}^{100}\mathrm{Mo}{(}^{18}\mathrm{O}, 5n)$ reaction at 94 MeV using the Chalk River $8\ensuremath{\pi}$ array. Three decoupled $(\ensuremath{\Delta}I=2)$ rotational bands extending to spins $I$ in the range $(63/2--69/2)\ensuremath{\Elzxh}$ have been identified and connected to known low-lying states. Experimental observations for the most extended band have been interpreted as evidence for smooth band termination. Theoretical calculations performed within a configuration-dependent shell-correction approach suggest that all three bands are built upon deformed two-particle--two-hole proton excitations across the $Z=50$ shell gap.

Lifetimes of low-lying states in {sup 125,127}La nuclei were measured using the recoil distance method. The nuclei were produced by the {sup 94}Mo({sup 35}Cl,2p2n) and {sup 112}Cd({sup 19}F,4n) reactions, respectively. Experimental results were described in the framework of the core quasiparticle coupling model. It was found that the observed bands can be reasonably well described as {pi}g{sub 7/2}, {pi}g{sub 9/2}, and {pi}h{sub 11/2} quasiparticle configurations coupled to elongated ({beta}{sub 2}{approx}0.28) triaxial cores. No evidence for a rapid change of the nuclear shape in the {pi}h{sub 11/2} band in {sup 127}La is seen in our data. {copyright} {ital 1997} {ital The American Physical Society}

High-spin structures of 119 I have been studied by using 13 C and 15 N induced reactions. In all, fifteen ΔI = 1 or 2 bands belonging to 119 I were found. No evidence was found for bands with collective oblate shape, instead, all the observed rotational bands were interpreted to possess a collective prolate shape. A rich tapestry of noncollective states of both negative and positive parity was observed. Based on TRS calculations various configurations at β 2 ≈ 0.17 and γ = 60° were assigned to these states.

Numerical simulation of coupled bath/metal magnetohydrodynamics (MHD) and MHD stability analysis allow the optimization of anode set pattern with respect to minimal cell disturbance. The contribution of anode gas-induced forces and the impact on the flow field are discussed.

A general formula is given for correlation between two polarized gamma rays ( γ 1 and γ 2 ) emitted in a cascade from an oriented (for example, due to a heavy ion reaction) nucleus. It allows us or one to calculate the angular correlation between: (a) Linear polarizations of γ 1 and γ 2 . (b) Polarization of γ 1 and direction of γ 2 or vice versa. (c) Directions of γ 1 and γ 2 (DCO). The formula, discussed in detail for the case (b), can be used in the analysis of data coming from the modern multidetector gamma ray spectrometers that contain new generation detectors (e.g. CLOVER) sensitive to the polarization. The analysis of polarization together with DCO ratio can lead to a unique spin/parity assignment and a mixing ratio determination.

Excited states of the {sup 125}La and {sup 127}La nuclei were populated following {sup 112}Sn({sup 16}O,{ital p}2{ital n}) and {sup 112}Cd({sup 19}F,4{ital n}) fusion-evaporation reactions, respectively, and investigated using methods of in-beam {gamma}-ray spectroscopy. Five collective bands in {sup 125}La, and eleven collective bands in {sup 127}La were observed. The spin and/or parity assignments of excited states in these nuclei were based on angular-correlation and linear-polarization measurements. The experimental data are discussed and compared to the results of self-consistent total-Routhian-surface calculations including quadrupole pairing. {copyright} {ital 1996 The American Physical Society.}

Preliminary results of DSA lifetime measurements in the partner bands of 124Cs are presented. The 124Cs nucleus was produced in the 114Cd(14N,4n)124Cs reaction at the Heavy Ion Laboratory of the University of Warsaw. A phenomenon of spontaneous time-reversal symmetry breaking in 124Cs nucleus is discussed. Appearance of a critical rotational frequency being the point of phase transition to time-reversal symmetry breaking configurations is suggested.

Excited states of the $^{146}\mathrm{Tb}$ nucleus have been studied using $\ensuremath{\gamma}$-ray and electron spectroscopy in off-beam and in-beam modes following $^{112}\mathrm{Sn}$($^{40}\mathrm{Ar}$,$3n3p$) reaction with the use of the OSIRIS-II, HPGe detector array and the conversion electron spectrometer. The multipolarity of the 343 keV transition deexciting the $({7}^{\ensuremath{-}})$ level in $^{146}\mathrm{Tb}$ shows mainly an $E2$ nature and the first excited state above the 23 s isomer is assigned as a $({5}^{\ensuremath{-}},{6}^{\ensuremath{-}})$ state. The log $\mathit{ft}$ values have been deduced for 11 ${\ensuremath{\beta}}^{+}/$EC transitions populating excited states in $^{146}\mathrm{Gd}$. The systematic behavior of spins and parities of the long-lived levels at $0+x$ keV and the first excited states above them in the $N=81$ isotones $^{146}\mathrm{Tb}$, $^{148}\mathrm{Ho}$, and $^{150}\mathrm{Tm}$ is discussed.

The richness of information pertaining to El, E2, E3 and M1 interaction deduced from Coulomb excitation experiments is illustrated. E2 and particularly M1 transition probabilities in 128 Xe are presented. Large set of E3 and E1 additionally to E2 transition probabilities in 226 Ra are shown.

An odd-odd nucleus is treated as the core-particle-hole system. The core is described by the Bohr Hamiltonian. Different collective potentials of the core are investigated. The odd particle and hole are assumed to be in the symmetric [proton h11/2]x[neutron hole h11/2] configuration. Signatures of chirality in the odd-odd nucleus spectra are observed. The sufficient condition for the appearance of signatures of chirality in the core-particle-hole system is the alpha-symmetry of the core provided the particle-hole configuration of the odd valence particles is symmetric., 9 pages, 7 figures. Presented at the 17th Nuclear Physics Conference "Marie and Pierre Curie" on "Symmetry and Symmetry Breaking in Nuclear Physics", Kazimierz Dolny, 22-26 September 2010, Poland. Accepted for publication in Int. Jour. of Mod. Physics E

The excited states of {sup 148}Ho and {sup 149}Ho isotopes are studied using gamma-ray and electron spectroscopy in off-beam and in-beam modes following {sup 112,114}Sn({sup 40}Ar,xnyp) reactions. Experiments include measurements of single gamma-rays and conversion electron spectra as well as gamma-gamma, electron-gamma, gamma-t, and gamma-gamma-t coincidences with the use of the OSIRIS-II 12-HPGe array and conversion electron spectrometer. Based on the present results, the level schemes of {sup 148}Ho and {sup 149}Ho are revised and significantly extended, up to about 4 and 5 MeV of excitation energy, respectively. Spin and parity of 5{sup -} are assigned to the 9.59-s isomer in {sup 148}Ho based on conversion electron results. Previously unobserved gamma rays feeding the 10{sup +} isomer in {sup 148}Ho and the 27/2{sup -} isomer in {sup 149}Ho nuclei are proposed. Shell-model calculations are performed. Possible core-excited states in {sup 149}Ho are discussed.

Properties of chiral bands in an odd-odd nucleus, which is treated as a system of an even-even core and a pair of particles in the πh 11/2 ⊗ υh 11/2 -1 configuration, are calculated in the frame of the Core-Particle-Hole Coupling (CPHC) model with either a rigid triaxial or a soft core. The results of calculations for the two different cores are compared. The properties of the nucleus with the rigid, maximally triaxial ( γ = 30°and with the entirely soft core are qualitatively very similar.

The decay of the \(\ensuremath I^{\pi}=K^{\pi}=8^{-}\) isomeric state at 2340keV in 132Ce has been investigated in the 120Sn(16O, 4n)132Ce reaction. The measurements were carried out in e -\( \gamma\) and \( \gamma\) -\( \gamma\) coincidence modes using an electron spectrometer coupled to the OSIRIS II gamma-ray array at the Heavy Ion Laboratory of the University of Warsaw. Experimentally obtained internal conversion coefficients for the \(\ensuremath 8^{-} \rightarrow 6^{+}\) and \(\ensuremath 8^{-} \rightarrow 5^{+}\) transitions allowed the multipolarities, mixing ratios, reduced transition probabilities and hindrance factors to be determined.

We describe the basic aspects of a new, self-consistent Green-function method which allows to calculate the density of states, electron density, and related quantities for a localized perturbation (e.g. an isolated adsorbate or an intrinsic surface defect) at a crystal surface. The method is based on the density-functional theory and combines several ideas from recent theoretical developments, as, for example, from the layer-KKR Green-function method, from ab-initio pseudopotential theory, and from the self-consistent defect-Green-function method. Two applications of the method are presented (S on Pd(1 0 0) and Na on Al(1 0 0)) in order to demonstrate its efficiency and to address a recent controversial discussion concerning the nature of the bonding of alkali adsorbates on metals at very low coverage (Θ → 0).

For a level scheme investigation of ^{142}Gd an experiment with the $\gamma$-spectrometer EUROBALLIII has been carried out and lifetimes have been measured with EUROBALL IV using the Doppler-shift attenuation method. The high-spin states have been populated in these experiments by means of the ^{99}Ru(^{48}Ti, 2p3n) reaction at a beam energy of 240MeV and the ^{114}Sn(^{32}S, 2p2n) reaction at 160MeV, respectively. Reduced E2 transition probabilities B(E2) were determined for 15 members of four quadrupole bands. For the interpretation of the positive-parity even-spin quadrupole bands, calculations in the cranked Nilsson-Strutinsky as well as interacting boson models have been performed. From the former calculations it was concluded that the high-spin states of the (+ , 0)_{1} band in ^{142}Gd represent a triaxial nucleus rotating around the longest principal axis.

High spin states in 126Ce and 127Pr were populated via heavy ion reactions with 182-MeV 35Cl projectiles on a thick 96Ru target. Prompt γ–γ coincidences were measured. New states in 126Ce and 127Pr were found. The results are discussed in the framework of the core–quasiparticle coupling model.

The nuclear structure of the odd Mo-105 and Mo-107 isotopes was reinvestigated in the present work. The excited levels of Mo-105 were studied by observing prompt gamma rays emitted after the spontaneous fission of Cm-248 with the EUROGAM2 multidetector array. The already well-studied level structure of Mo-107 was also completed by a search for microsecond isomers. For this purpose, this nucleus was produced by the thermal-neutron-induced fission reaction at the ILL reactor, in Grenoble. We have shown that the experimental level energies and the gamma-decay patterns are well reproduced by simple particle-rotor calculations, assuming that these nuclei have an asymmetric shape. The shapes of the odd and even Mo are compared in the neutron range N=62-66.

The results of the Doppler-shift attenuation method lifetime measurements in partner bands of 128 Cs and 132 La are presented. Experimental reduced transition probabilities in 128 Cs are compared with theoretical calculations done in the frame of the core-quasiparticle coupling model. The electromagnetic properties, energy and spin of levels belonging to the partner bands show that 128 Cs is the best known example revealing the chiral symmetry breaking phenomenon.

Excited states in La-149, populated in the spontaneous fission of Cm-248, were studied with the EUROGAM2 array. A new Delta I = 2 band found in La-149 is interpreted as the alpha = -1/2 branch of the pi 3/2(-) [402] configuration. The bandhead has spin 7/2(-) because the 3/2(-) and 5/2(-) levels are pushed up by the Coriolis interaction. The 7/2(-) level is located not higher than 30 keV above the ground state and may form a long-lived isomer if spin and parity of the g.s. is 3/2(+).

Excited states in {sup 113}In were populated via the reactions {sup 100}Mo({sup 18}O,p4n){sup 113}In and {sup 110}Pd({sup 7}Li,4n){sup 113}In. The two known {delta}J=2 intruder bands, based on the {pi}g{sub 7/2}xd{sub 5/2} and {pi}h{sub 11/2} orbitals, have been extended by 8({Dirac_h}/2{pi}) to spins (49/2{sup +})({Dirac_h}/2{pi}) and (55/2{sup -})({Dirac_h}/2{pi}), respectively. The previous finding of three sequences of {delta}J=1 {gamma}-ray transitions has been confirmed. A self-consistent cranked shell-model calculation gives a good description of the contrasting alignment patterns of the two {delta}J=2 intruder bands. The intruder bands, the known sequences of M1 transitions, and spherical levels together represent a coexistence of three different excitation modes in this nucleus.