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The high-spin structure of deformedN = Z nuclei inf7/2 shell is presented. The experimental data obtained with the 4π γ-ray spectrometer is compared with large-scale shell model calculations. In odd-odd self-conjugate nuclei, bothT = 0 andT = 1 band-like structures have been observed.

High-spin states in 45Sc, 45Ti and 43Ca were studied by means of multiple γ- and γ-recoil-coincidences with the use of the GASP array and the Recoil Mass Spectrometer. The nuclei were populated in the 60 MeV 18O +30Si reaction. For the DSAM lifetime measurement the 35Cl +12C reversed kinematics reaction was used. In the article, a complete description of the experimental techniques used in course of the performed experiments is presented. The level schemes and the detailed information on the observed state properties, including B(M1) and B(E2) transition rates are inserted as well as their shell model interpretation.

Intermediate mass fragments (IMF) and light particles emitted from the Ni-58 + Ni-58 reaction at a beam energy of 375 MeV have been studied. The fragments and light particles were measured in coincidence with 4 pi gamma-ray spectrometer. The Z=6 (C) kinetic energy spectra and the distribution of the final nuclei in coincidence with the emitted C are well described by Hauser-Feshbach calculations extended to many channels. A detailed study of C-Psi and 3 alpha-gamma correlations indicate a strong selectivity of the IMF decay. Our results indicate that the IMF can populate nuclei that are not accessible via multiple light particle (Z

The quadrupole moments of highly deformed bands in ${}^{134,135}\mathrm{Nd}$ and ${}^{131}\mathrm{Ce}$ have been determined using the Doppler-shift attenuation method. The obtained ${Q}_{0}$ values show no clear dependence on the number of occupied $\ensuremath{\nu}{i}_{13/2}$ intruder orbitals. Cranked shell model calculations indicate that the charge-quadrupole moments of the highly deformed bands decrease with increasing spin. The expected increase in deformation induced by the $\ensuremath{\nu}{i}_{13/2}$ orbital in two bands of ${}^{134}\mathrm{Nd}$ is attenuated by a rotation-induced shrinking effect driving the nucleus towards smaller deformation.

Following the commissioning of the PRISMA large-acceptance spectrometer, installed at the Laboratori Nazionali di Legnaro (LNL), an international nuclear-structure collaboration has started to develop a large γ-ray setup to be installed in the target position of the spectrometer. The array is based on the EUROBALL composite CLOVER detectors. In this contribution the CLOVER detector array is described and its expected performance figures discussed. This new setup, by using the high-intensity heavyion beams provided by the LNL ALPI linac, will push the study of nuclear structure towards moderately neutron-rich nuclei by means of quasi-elastic and deep inelastic reactions.

The structure of Kr-72 has been investigated at GASP through the Ca-40(Ca-40,2 alpha) reaction at a beam energy of 160 MeV using the 4 pi ISIS Si-ball for reaction channel selection. The level scheme has been extended up to an excitation energy of approximate to 8.5 MeV. The spins and parities of the observed levels are assigned tentatively. The observed band shows the predicted change from oblate to prolate shape. The four quasi-particle g(9/2) alignment is found to be significantly delayed in rotational frequency with respect to the heavier Kr isotopes. Such a delay contradicts the predictions of standard mean-field calculations and may reflect either additional correlations in the T = 0 pairing channel or coupling to vibrational degrees of freedom or both. (C) 1997 Elsevier Science B.V. (Less)

A 4π Si-ball detector system has been constructed as a trigger device for the γ-ray spectrometer GASP. The construction and operation of the detector is reported, together with a brief description of the electronics and of the data acquisition system used. Results are presented for the 32S + 40Ca reaction at 140 MeV of32S beam energy.

The reaction {sup 58}Ni({sup 28}Si,2n{gamma}) at 90 MeV incident energy has been used to populate the N=Z nucleus {sup 84}Mo. The GASP array was used together with the ISIS Silicon ball, which allowed a subtraction of the charged particle channels in the {gamma}-{gamma} coincidences. The only known transition 2{sub 1}{sup +}{r_arrow}0{sub 1}{sup +} of 443.8 keV in {sup 84}Mo has been found in coincidence with a {gamma} ray of 673.5{plus_minus}0.4 keV which was assigned as the second (4{sub 1}{sup +}{r_arrow}2{sub 1}{sup +}) yrast transition. The behavior of the resulting yrast line indicates that {sup 84}Mo is a transitional nucleus. The correlation between the excitation energies of the 2{sub 1}{sup +} and 4{sub 1}{sup +} levels of the N=Z nuclei reveals a systematic deviation from the average behavior defined by all collective even-even nuclei. {copyright} {ital 1997} {ital The American Physical Society}

The structure of theN=Z nuclei60Zn,62Ga,64Ge, and72Kr has been investigated at GASP. Total Routhian surface (TRS) calculations have been performed for theN=36, 38 and 40 Kr isotones. In the case of72Kr the four quasi-particleg9/2 alignment is observed to be significantly delayed in rotational frequency with respect to the heavier Kr isotopes. Such a delay contradicts the predictions of mean field calculations and may be viewed as the first sign of additional correlations in theT=0 pairing channel.

The reaction has been studied , exploring the possibility of producing hot nuclei with low-angular momentum, in the mass region , suitable for studies of the level-density parameter. The possibility of using the energy of the inelastically scattered particles to determine the excitation energy deposited in the target nucleus has been checked by measuring evaporated charged particles, neutrons, fission fragments and -rays. Comparison of the data with results from the fusion reaction and statistical model calculations seems to indicate that, in the case of inelastic scattering, not all the energy dissipated in the collision is normally deposited as thermal excitation in the target nucleus. From evaporated proton spectra there is evidence for a strong pre-equilibrium component even at the most backward angles.

High spin states in123,124I were populated via the116Cd(11B,xn) reaction at 38 MeV bombarding energy and via the110Pd(18O,pxn) reaction at 75 MeV energy. γ-ray energies, intensities, γγ coincidences and DCO ratios were measured with the GASP spectrometer. The level schemes were extended considerably. Band terminations were observed in both nuclei. In123I the rotational band, which is built on the πh 11/2 single-particle state was extended to spinI π=(35/2)−; at higher spin the level spacings and the feeding pattern were found to become irregular, indicating a structure change. The (39/2)− state and the higher-lying (43/2)− level were interpreted as aligned oblate states. In124I a decoupled band was found to terminate in the same spin region. Total Routhian surface calculations were performed which support the occurrence of a band termination.

High-spin states in ${}^{50}$Cr have been investigated with the reaction ${}^{24}\mathrm{Mg}{(}^{32}\mathrm{S},\ensuremath{\alpha}2p)$ at 130 MeV bombarding energy, using the 4$\ensuremath{\pi}$ GASP $\ensuremath{\gamma}$-ray array plus the 4$\ensuremath{\pi}$ charged-particle detector ISIS. The level scheme has been extended up to the 18${}^{+}$ state at 17.954 MeV excitation energy. Several high-spin states which deexcite by emitting high energy $\ensuremath{\gamma}$-rays have been identified. A second backbending is observed at $I=18\ensuremath{\Elzxh}$, well above the 14${}^{+}$ state which exhausts the total spin available in a pure ${(f}_{7/2}{)}^{10}$ configuration.

High-spin states in the nucleus ${}^{123}$I were populated by the ${}^{110}$Pd${(}^{16}$O,$p4n)$ reaction at 75 MeV. $\ensuremath{\gamma}$-ray energies, intensities, $\ensuremath{\gamma}$-$\ensuremath{\gamma}$ coincidences, and directional correlation ratios were measured. The rotational band built on the $\ensuremath{\pi}{h}_{11/2}$ single-particle state was extended to spin ${I=35/2}^{\ensuremath{-}}$; at higher spin the level spacings and the feeding pattern were found to become irregular, indicating a sudden change of structure. The 39/2${}^{\ensuremath{-}}$ state and a higher-lying ${43/2}^{\ensuremath{-}}$ level were interpreted as aligned oblate states, in line with the systematics of the lighter odd-$A$ iodine isotopes. Total Routhian surface calculations were performed and were found to support the occurrence of a band termination. Higher-lying levels that feed the ${h}_{11/2}$ band were identified, reaching spin $Ig~47/2$ and an excitation energy of about 9 MeV.

High-spin states in {sup 162}Lu and {sup 164}Lu have been studied by means of in-beam {gamma}-ray spectroscopy techniques using the multidetector array GASP. The excited states have been populated through the {sup 139}La({sup 28}Si,5n){sup 162}Lu and {sup 139}La[{sup 29(30)}Si,4(5)n]{sup 164}Lu reactions. Level schemes were constructed for both nuclei. Configurations for the rotational bands have been discussed. Alignments, band crossing frequencies, and B(M1)/B(E2) ratios have been analyzed in the framework of the cranking model. The systematic evolution of the signature inversion in the {pi}h{sub 11/2}{circle_times}{nu}i{sub 13/2} structure is reviewed. {copyright} {ital 1997} {ital The American Physical Society}

The ridge structure at {Delta}E{sub {gamma}}={plus_minus}30 keV, observed previously in the reaction 187 MeV {sup 37}Cl + {sup 120}Sn and attributed to an hyperdeformed nuclear shape, has been studied in a high statistics proton-{gamma} coincidence experiment. The presence of the ridge is confirmed but it is correlated to a set of {gamma}-ray energies different from those proposed in earlier works. Some discrete transitions associated with this structure, which accounts for only {approximately}3{times}10{sup {minus}5} of the fusion evaporation cross section, are proposed. {copyright} {ital 1997} {ital The American Physical Society}

Five superdeformed (SD) bands have been identified in 144Gd with the GASP array using the reaction 100 Mo + 48 Ti . The J(2) moments of inertia of the four excited SD bands are flat as a function of rotational frequency, indicating the blocking of the N = 6 proton crossing observed in the yrast SD band. According to cranked shell model calculations, the excited bands have two-quasiproton configurations with one proton in the N = 6 orbital and the other in each signature partner of the [404]9 2 + or [411]3 2 + orbitals, lying above the Z = 64 gap. The interpretation of the excited SD bands in terms of proton excitations points to the high stability of the N = 80 shell closure at SD shapes. The population of the yrast SD band as a function of the beam energy has been also investigated. Our data shows that the intensity of the yrast SD band is not configuration dependent, being comparable to that of yrast SD bands in the neighboring nuclei. By comparing experimental and theoretical alignments, spins and configurations are assigned to all observed SD bands in the A = 140–150 region.

Three bands consisting of dipole M1 and quadrupole E2 crossover transitions have been identified in 134 Nd using the GASP array and the 110 Pd( 28 Si, 4n) reaction at 130 MeV. Calculations with the projected shell model are used to assign configurations to the different bands and to infer their K -composition. The properties of the band built on the I π = 8 − isomer confirm the previously assigned two-quasineutron [404] 7 2 + ⊗ [514] 9 2 − configuration of the isomeric state. The other two bands are interpreted as coexisting prolate and oblate four-quasiparticle configurations.

Neutron-rich sdf shell nuclei have been produced in deep-inelastic processes during collision of 230 MeV {sup 37}Cl ions on a thick {sup 208}Pb target. The in-beam as well as off-beam {gamma}-{gamma} coincidence data yielded new spectroscopic information on some hard-to-access N=18,19 isotones. A new 27 ns isomer at 5583 keV in {sup 32}Si has been located. A candidate for the negative parity state 4{sup {minus}} has been identified above the 200 ns isomer in {sup 32}Al. {copyright} {ital 1997} {ital The American Physical Society}

The structure of Sn-105 has been investigated through the Cr-50(Ni-58,2pn) reaction at a beam energy of 210 MeV. In addition to an extension of the spherical level scheme a regular sequence of dipole transitions has been found. The states of the dipole band are suggested to be built on a neutron hf(11/2)(2) excitation coupled to proton particle-hole states, which polarize the core to a slightly prolate shape. The experimental results are in agreement with the prediction of tilted axis cranking calculations, which satisfactorily explain the properties of the band.

The study of superdeformation in nuclei around the nucleus 144Gd, which can be considered as doubly-closed at superdeformed shape, provided detailed knowledge about the structure of superdeformed bands in this region. The chain of Gd isotopes showing superdeformation could be extended to 143Gd. Since highly-deformed bands are known in 139,141Gd, it appears that the transition between the regions of superdeformed nuclei with A ≈ 150 and of highly-deformed nuclei with A ≈ 130 is rather sharp and takes place around N = 78 as theoretically predicted. In 144Gd four excited superdeformed bands have been found in addition to the yrast superdeformed band. They form two pairs of signature partner bands of π6 1 π[404]9 2ν7 0 and π6 1 π[411]3 2ν7 0 configurations. In 145Gd for the first time two crossings have been observed in a superdeformed band, which are assigned to the alignment of an i 13 2 proton pair and a subsequent crossing of the i 13 2 [642]5 2 and i 11 2 [651]1 2 neutron orbitals, respectively.

${}^{186}$Ir has been restudied through the ${}^{180}$Hf${(}^{11}$B,5$n)$ reaction at 65 MeV using in-beam $\ensuremath{\gamma}$-ray and conversion-electron spectroscopy. The unfavored component of the doubly decoupled band was established and shown to be consistent with a description in terms of the $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}[\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{411}1/2,3/2]$ structure, i.e., the coupling of an aligned proton and a neutron pseudospin doublet.

Lifetimes of the low-lying (11/2-) states in 63,65Co have been measured employing the recoil distance doppler shift method (RDDS) with the AGATA γ-ray array and the PRISMA mass spectrometer. These nuclei were populated via a multinucleon transfer reaction by bombarding a 238U target with a beam of 64Ni. The experimental B(E2) reduced transition probabilities for 63,65Co are well reproduced by large-scale shell-model calculations that predict a constant trend of the B(E2) values up to the N=40 67Co isotope

Recoil distance Doppler-shift and Doppler-shift attenuation lifetime measurements were carried out for levels in ${}^{155}$Dy through the coincident detection of $\ensuremath{\gamma}$ rays. Twenty-six lifetimes, most of them for the first time, were determined using the differential decay curve method for the analysis of the data. At low and medium spins, particle-plus-triaxial-rotor calculations reveal different quadrupole deformations for the one-quasineutron bands in this transitional nucleus. At high spin, the reduced $B(E2)$ transition probabilities confirm with a better precision the results of a previous study implying decreased collectivity with increasing spin.

The K hindrance to the gamma decay is studied in the warm rotating W-174 nucleus, focusing on the weakening of the selection rules of the K quantum number with increasing excitation energy. W-174 was populated by the fusion reaction of Ti-50 (at 217 MeV) on a Te-128 target, and its gamma decay was detected by the AGATA Demonstrator array coupled to a BaF2 multiplicity filter at Laboratori Nazionali di Legnaro of INFN. A fluctuation analysis of gamma coincidence matrices gives a similar number of low-K and high-K discrete excited bands. The results are compared to simulations of the gamma-decay flow based on a microscopic cranked shell model at finite temperature in which the K mixing is governed by the interplay of Coriolis force with the residual interaction. Agreement between simulations and experiment is obtained only by hindering the E1 decay between low-K and high-K bands by an amount compatible with that determined by spectroscopic studies of K isomers in the same mass region, with a similar trend with excitation energy. The work indicates that K mixing due to temperature effects may play a leading role for the entire body of discrete excited bands, which probes the onset region of K weakening.

International audience; The nuclear structure of 69Cu has been investigated by means of the (d,3He) transfer reaction at the Orsay tandem in direct kinematics using a deuteron beam at Ed = 27 MeV and a target of 70Zn isotopically enriched to 95.4%. The 3He of interest from the transfer reaction were detected with the split-pole spectrometer at different angles in the laboratory frame in order to perform angular distributions and assign the angular momentum for each populated state in 69Cu. In this paper, the transferred angular momenta of the populated states will be presented.

Isomeric ratios have been measured for high-spin states in Po-198,200,206,208(84), At-208,209,210,211(85), Rn-210,211,212,213,214(86), Fr-208,211,212,213,214(87), Ra-210,211,212,214,215(88), and Ac-215(89) following the projectile fragmentation of a 1 AGeV U-238 beam by a Be-9 target at GSI Helmholtzzentrum fur Schwerionenforschung. The fragments were separated in the fragment separator (FRS) and identified by means of energy loss and time-of-flight techniques. They were brought to rest at the centre of the RISING gamma-ray detector array and intensities of gamma rays emitted in the decay of isomeric states with half-lives between 100 ns and 40 mu s and spin values up to 55/2 (h) over bar were used to obtain the corresponding isomeric ratios. The data are compared to theoretical isomeric ratios calculated in the framework of the abrasion-ablation model. Large experimental enhancements are obtained for high-spin isomers in comparison to expected values. (C) 2013 Elsevier B.V. All rights reserved.

International audience; The neutron-rich isotopes of tungsten, osmium and platinum have different shapes in their ground states and present also shape transitions phenomena. Spectroscopic information for these nuclei is scarce and often limited to the gamma rays from the decay of isomeric states. For the neutron-rich even-even osmium isotopes Os-194 and Os-198, a shape transition between a slightly prolate deformed to an oblate deformed ground state was deduced from the observed level schemes. For the even-even nucleus lying in between, Os-196, no gamma ray transition is known. In order to elucidate the shape transition and to test the nuclear models describing it, this region was investigated through gamma-ray spectroscopy using the AGATA demonstrator and the large acceptance heavy-ion spectrometer PRISMA at LNL, Italy. A two-nucleon transfer from a Pt-198 target to a stable Se-82 beam was utilized to populate medium-high spin states of Os-196. The analysis method and preliminary results, including the first life-time measurement of isomeric states with AGATA, are presented.

This work has been partly financed by the European Union Seventh Framework Program FP7/2007-2013 under Grant Agreement No. 262010 ENSAR, the Polish MNiSW under Grant No. DPN/N190/AGATA/2009, the Spanish Ministerio de Ciencia e Innovacion under Contract No. FPA2011-29854-C04, and ´ the BMBF under Grant Nos. 05P12RDFN8 and 06DA9040I.

High-spin states in ${}^{184}$Au have been investigated by means of in-beam $\ensuremath{\gamma}$-ray spectroscopy techniques using the multidetector array of GASP. Excited states of ${}^{184}$Au were populated via the ${}^{159}$Tb(${}^{29}$Si, 4$n$$\ensuremath{\gamma}$) reaction at a beam energy of 140 MeV. The previously known bands based on the $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}7/{2}^{\ensuremath{-}}[514]$, $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}1/{2}^{\ensuremath{-}}[521]$, $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$, and $\ensuremath{\pi}{i}_{13/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ configurations have been extended. Three new rotational bands have been identified and assigned as the prolate $\ensuremath{\pi}1/{2}^{+}[660]\ensuremath{\bigotimes}\ensuremath{\nu}7/{2}^{\ensuremath{-}}[514]$ and $\ensuremath{\pi}11/{2}^{\ensuremath{-}}[505]\ensuremath{\bigotimes}\ensuremath{\nu}7/{2}^{\ensuremath{-}}[514]$ and oblate $\ensuremath{\pi}{h}_{11/2}^{\ensuremath{-}1}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}^{\ensuremath{-}1}$ configurations, respectively. Experimental aligned angular momenta, band-crossing frequencies, and electromagnetic properties have been analyzed in the framework of the cranked shell model. Low-spin signature inversion has been observed in the prolate $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ and $\ensuremath{\pi}{i}_{13/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ and oblate $\ensuremath{\pi}{h}_{11/2}^{\ensuremath{-}1}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}^{\ensuremath{-}1}$ bands of ${}^{184}$Au.

Neutron-rich nuclei in the lead region, beyond N = 126, have been studied at the FRS-RISING setup at GSI, exploiting the fragmentation of a primary uranium beam. Two isomeric states have been identified in Hg-210: the 8(+) isomer expected from the seniority scheme in the vg(9/2) shell and a second one at low spin and low excitation energy. The decay strength of the 8(+) isomer confirms the need of effective three-body forces in the case of neutron-rich lead isotopes. The other unexpected low-lying isomer has been tentatively assigned as a 3(-) state, although this is in contrast with theoretical expectations. (C) 2013 Elsevier B.V. All rights reserved.

WOS: 000314826000009, The response of AGATA segmented HPGe detectors to gamma rays in the energy range 2-15 MeV was measured. The 15.1 MeV gamma rays were produced using the reaction d(B-11,n gamma)C-12 at E-beam=19.1 MeV, while gamma rays between 2 and 9 MeV were produced using an Am-Be-Fe radioactive source. The energy resolution and linearity were studied and the energy-to-pulse-height conversion resulted to be linear within 0.05%.Experimental interaction multiplicity distributions are discussed and compared with the results of Geant4 simulations. It is shown that the application of gamma-ray tracking allows a suppression of background radiation caused by n-capture in Ge nuclei. Finally the Doppler correction for the 15.1 MeV gamma line, performed using the position information extracted with Pulse-shape analysis is discussed. (C) 2012 Elsevier B.V. All rights reserved., European Union [262010-ENSAR]; MINECO Spain [AIC-D-2011-0746, FPA2011-29854]; Generalitat Valenciana, Spain [PROME-TEO/2010/101]; German BMBF [06K-167, 06KY205I], This research has received funding from the European Union Seventh Framework Program FP7/2007-2013 under grant Agreement no. 262010-ENSAR. A.G. activity has been supported by the MINECO Spain, under grants AIC-D-2011-0746, FPA2011-29854 and by and Generalitat Valenciana, Spain, under grant PROME-TEO/2010/101. We acknowledge the support by the German BMBF under Grants 06K-167 and 06KY205I.

Fusion cross sections and mean angular momenta have been measured for the four systems 28Si+94,100Mo and 58,64Ni+64Ni and can be explained in the framework of the coupled-channels (CC) approach. In particular the influence of 2n-transfer channels with positive Q-values shows up. The direct relation between excitation function and angular momenta has been verified.

The high-spin structure of 104Cd has been studied through the 50Cr(58Ni,4p) reaction at a beam energy of 220 MeV. The level scheme has been extended up to an excitation energy of 11.9 MeV. Four collective structures have been identified based on two-quasineutron configurations. The low-lying states of both parities, as well as the main ΔI=2 regular structures observed at high spin, are described in the framework of the interacting boson-fermion model with broken pairs.

The level scheme of the doubly odd 136Pr nucleus has been investigated via the 136Ce(p,n), 122Sn(19F,5n) and 110Pd(30Si,p3n) reactions at beam energies of 14, 84 and 125 MeV, respectively. A complex decay scheme has been established for the 90 ns isomeric level with Ex = 594.7 keV and Jπ = 6+. The two previously reported bands, one based on the πh 11 2 ⊗ νh 11 2 configuration and one with suggested negative parity consisting of only dipole transitions, have been extended at higher spins and connected firmly to the 6+ isomer. Six new bands have been also identified: two consist of strong dipole and crossover quadrupole transitions, whereas the other four, very weakly populated, consist of only quadrupole transitions. The observed level structures are compared to theoretical calculations performed within the interacting boson model for odd-odd nuclei (IBFFM) and the cranked shell model. The experimental B (M1) B (E2) ratios of the yrast band are well reproduced by the IBFFM calculations, while those of the other semi-decoupled structures are in good agreement with the values obtained from the semiclassical model of Donau.

Six superdeformed (SD) bands have been observed in the nucleus {sup 148}Gd using the {gamma}-spectrometer GASP. The structure of the observed SD bands is discussed within the concept of cranked-Strutinsky-type calculations including pairing interaction. For the configuration assignments two different parametrizations of the Woods-Saxon potential are compared. Five of the observed SD bands are described in terms of quasiparticle configurations, whereas one is suggested to have vibrational-like structure. From this data a {Delta}{ital I}=2 staggering in the rotational spectrum of the yrast SD band also has been observed. {copyright} {ital 1996 The American Physical Society.}

The neutron deficient 141Tb nucleus has been studied with the 92Mo (54Fe, alphap) reaction at 240-MeV incident energy and the multidetector array GASP. For the yrast pih11/2 decoupled band, excited states up to 6.7 MeV and spin up to 47/2- have been observed. This band presents an upbend at rotational frequency of omega = 0.38 MeV due to the alignment of h11/2 protons. The results are discussed in terms of the Cranking model.

High-spin states in 184Au have been populated via the 149Sm(29Si, 4n?) 184Au reaction at a beam energy of 140?MeV. Three- or higher-fold ?-ray coincidences have been measured using the multidetector array of GASP. A rotational band built on the 11? oblate ?h11/2?1??i13/2?1 structure has been newly observed, similar to those reported in 186?194Au. This result extends the knowledge of shape coexistence to the currently lightest odd?odd Au isotope.

The neutron-deficient nucleus Kr-75 has been studied in two EUROBALL experiments. The analysis yielded a considerably extended level scheme including two newly observed excited high spin bands. The results are interpreted in the framework of the cranked Nilsson-Strutinsky approach. The calculations compare well to the experimentally established level scheme and predict the nucleus to be mainly prolate or triaxially deformed at high spin. Evidence for an oblate-prolate shape coexistence could not be found at high spin. ©2012 American Physical Society, Supported by the German BMBF under Contract No. 06K167.

Experimental data collected so far demonstrate that the population of superdeformed (SD) structures in nuclei with mass A∼150 is influenced by the asymmetry in the entrance channel of the reaction. Furthermore, evidences for the population of hyperdeformed (HD) structures in the same mass region have been obtained only when charged particles are emitted in the evaporation chain. Dynamical model calculations show that in the reactions used to populate SD bands the equilibration times of the compound nuclei are not very sensitive on the mass asymmetry of the entrance channel. A qualitative understanding of both phenomena (SD and HD) is obtained assuming a link between the population of evaporation residues at very high spin and the dynamical hindrance of fission. Recent experimental results obtained in this field at the GASP spectrometer are presented for the case of the152Dy nucleus populated in the37Cl+120Sn reaction. Proton and alpha particle spectra in coincidence with SD structures have been obtained. A sizeable difference is evidenced between alpha particle spectra in coincidence with SD and normally deformed structures.

A project has been realized to link the CAMEL recoil mass spectrometer to the GASP γ-spectrometer in order to perform high resolution and efficiency γ-recoil coincidence measurements. To preserve high flexibility and autonomy in the operation of the two complex apparatus a rough factor two of reduction in the overall heavy ion transmission was accepted in designing the optics of the particle transport from the GASP center to the CAMEL focal plane. The coupled configuration has been tested with the fusion reaction 58 Ni (E = 212 MeV ) + 64 Ni , obtaining a mass resolution of 1 300 and efficiency between ∼ 11% and ∼ 15% for different evaporation products.

Excited states in 157Dy have been studied by γ-γ coincidence measurements via the reaction 124Sn(36S,3n) at a beam energy of 155MeV. Lifetimes of the relatively lower-spin states in 157Dy were measured by means of the Recoil Distance Dopplershift technique in the coincidence mode. The experiment was performed at the Laboratori Nazionali di Legnaro with the GASP array and the Cologne plunger device. With the same setup a Doppler- shift attenuation (DSA) lifetime measurement was performed for the higher spin states. The Differential decay-curve method was applied for the lifetime determination.

Fusion-evaporation cross sections for $^{58}\mathrm{Ni}$ + $^{60}\mathrm{Ni}$ have been measured with high accuracy in the energy range around the Coulomb barrier. The data yield an "experimental distribution of fusion barriers" around 13 MeV wide, which displays structure characteristic of strong phonon couplings with two large well "resolved" peaks, and a smaller peak at lower energies, which is essential for fitting the low-energy cross section. This is obtained only when the target and projectile double-phonon excitations are taken into account. This is the first time that such complex surface vibrations have been identified in a fusion experiment.

Unfavored components of doubly decoupled bands are reported for the first time. They can be interpreted as having the pseudo-spin flipped relative to the orientation in the favored components, i.e. antialigned with respect to the rotation axis. In addition, the differences in consecutive transition energies along the favored and unfavored sequences are strikingly similar among them up to Iπ = 15+and 14+ respectively. This feature arises from a cancellation of differences in alignments and moments of inertia.

The results of the measurement of fusion cross sections σ fus and mean angular momenta l for the five systems 16 O+ 112 Cd, 28 Si+ 94,100 Mo and 58,64 Ni+ 64 Ni are reported. The direct comparison between the fusion excitation function and l ( E ) confirms consistency of the two independent observables. By analyzing the data in the framework of the coupled channels (CC) approach a good overall agreement between experiment and model predictions has been found. In particular the influence of 2n-transfer channels with positive Q-values is put in evidence.

Very proton rich nuclei in the A≈100 region have been investigated using the GASP array coupled with the Recoil Mass Spectrometer (RMS) and the GASP Si-ball. High-spin states of 105Sn and 103In nuclei formed with the reaction 58 Ni + 50 Cr at 210 MeV have been investigated up to ≈ 10 and 7 MeV of excitation energy respectively. We have confirmed the known excited states for both nuclei and extended to higher spin the level scheme. The experimental level schemes are compared with shell model calculations.

The nuclear structure of neutron-rich nuclei close to the double-magic nucleus 78Ni has been investigated by measuring the lifetime of excited states. In this contribution, it will be presented the lifetime of the Jπ = 7=2 excited state at 981 keV of the 71Cu isotope, measured using the AGATA Demonstrator coupled to the PRISMA spectrometer and the Köln plunger setup. This is the first time this combined setup has been used for a lifetime measurement., This work has been partially supported by the grants FPA2008-06419, FPA2008-03774, AIC10-D-000605, AIC-D-2011-0764 and Consolider CSD2007-00042 from the Spanish Government and by INFN Italy.

This work was partially supported by the European Community FP6, Structuring the ERA Integrated Infrastructure Initiative Contract No. EURONS RII3-CT-2004-506065, by MICINN, Spain (Contract No. FPA2011-29854), by IN2P3, France (Contract No. AIC-D-2011-648), by Comunidad de Madrid, Spain (Contract No. HEPHACOS S2009-ESP-1473), and by Generalitat Valenciana, Spain (Contract No. PROMETEO/ 2010/101). A. Gadea and E. Farnea acknowledge the support of MICINN, Spain, and INFN, Italy, through the AIC-D-2011-0746 bilateral action

This work was supported by the Italian Istituto Nazionale di Fisica Nucleare and partially by the Spanish MICINN (AIC10-D-000568 bilateral action and FPA2008-06419) and Generalitat Valenciana (Grant PROMETEO/2010/101). The work has also been partially supported by the Polish Ministry of Science and Higher Education (Grant No. N N202 309135)