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The NO cycle takes place in the deepest layer of a H-burning core or shell, when the temperature exceeds T {\simeq} 30 {\cdot} 106 K. The O depletion observed in some globular cluster giant stars, always associated with a Na enhancement, may be due to either a deep mixing during the RGB (red giant branch) phase of the star or to the pollution of the primordial gas by an early population of massive AGB (asymptotic giant branch) stars, whose chemical composition was modified by the hot bottom burning. In both cases, the NO cycle is responsible for the O depletion. The activation of this cycle depends on the rate of the 15N(p,{\gamma})16O reaction. A precise evaluation of this reaction rate at temperatures as low as experienced in H-burning zones in stellar interiors is mandatory to understand the observed O abundances. We present a new measurement of the 15N(p,{\gamma})16O reaction performed at LUNA covering for the first time the center of mass energy range 70-370 keV, which corresponds to stellar temperatures between 65 {\cdot} 106 K and 780 {\cdot}106 K. This range includes the 15N(p,{\gamma})16O Gamow-peak energy of explosive H-burning taking place in the external layer of a nova and the one of the hot bottom burning (HBB) nucleosynthesis occurring in massive AGB stars. With the present data, we are also able to confirm the result of the previous R-matrix extrapolation. In particular, in the temperature range of astrophysical interest, the new rate is about a factor of 2 smaller than reported in the widely adopted compilation of reaction rates (NACRE or CF88) and the uncertainty is now reduced down to the 10% level., Comment: 6 pages, 5 figures

The decay properties and the magnetic moment of the 548 keV isomeric state in 136Pr populated in the 122Sn (19F, 5n) reaction were investigated by pulsed beam γ-ray spectroscopy and TDPAD measurements using as host metallic Pt at room temperature. The determined characteristics of the isomeric state, T12 = 90(2) ns, Jπ = 4+ and g = + 0.570(19), are explained by assigning to it a dominant configuration π(1h112)⊗ν(1h112) and an extremely small contribution of configurations involving proton and neutron positive-parity orbits. Firm spin assignment for the upper energy collective structures can be deduced.

The even-even nucleus 128Nd was studied via in-beam γ-ray spectroscopy using the 40Ca + 82Mo reaction at 190 MeV. Two new bands were observed besides the yrast one, that has been extended up to spin 34+. Configurations were assigned to the three bands by analysing their rotational properties and by comparison with the neighboring even-even nuclei.

To investigate the possible X(5) character of {sup 122}Ba, suggested by the ground-state band energy pattern, the lifetimes of the lowest yrast states of {sup 122}Ba have been measured, via the recoil distance Doppler-shift method. The relevant levels have been populated by using the {sup 108}Cd({sup 16}O,2n){sup 122}Ba and the {sup 112}Sn({sup 13}C,3n){sup 122}Ba reactions. The B(E2) values deduced in the present work are compared to the predictions of the X(5) model and to calculations performed in the framework of the IBA-1 and IBA-2 models.

The {sup 15}N(p,{gamma}){sup 16}O reaction represents a breakout reaction linking the first and second cycles of the CNO cycles redistributing the carbon and nitrogen abundances into the oxygen range. The reaction is dominated by two broad resonances, at E{sub p}=338 and 1028 keV, and a direct capture contribution to the ground state of {sup 16}O. Interference effects between these contributions both in the low-energy region (E{sub p}

Proton captures on Mg isotopes play an important role in the Mg-Al cycle active in stellar $H$-shell burning. In particular, the strengths of low-energy resonances with $El200$ keV in $^{25}\mathrm{Mg}$($p,\ensuremath{\gamma}$)$^{26}\mathrm{Al}$ determine the production of $^{26}\mathrm{Al}$ and a precise knowledge of these nuclear data is highly desirable. Absolute measurements at such low energies are often very difficult and hampered by $\ensuremath{\gamma}$-ray background as well as changing target stoichiometry during the measurements. The latter problem can be partly avoided using higher-energy resonances of the same reaction as a normalization reference. Hence the parameters of suitable resonances have to be studied with adequate precision. In the present work we report on new measurements of the resonance strengths $\ensuremath{\omega}\ensuremath{\gamma}$ of the $E=214$, $304$, and $326$ keV resonances in the reactions $^{24}\mathrm{Mg}$($p,\ensuremath{\gamma}$)$^{25}\mathrm{Al}$, $^{25}\mathrm{Mg}$($p,\ensuremath{\gamma}$)$^{26}\mathrm{Al}$, and $^{26}\mathrm{Mg}$($p,\ensuremath{\gamma}$)$^{27}\mathrm{Al}$, respectively. These studies were performed at the LUNA facility in the Gran Sasso underground laboratory using multiple experimental techniques and provided results with a higher accuracy than previously achieved.

The transition strenghts for the low—lying levels of 122,124Ba have been determined analysing the Recoil Distance Doppler Shift data by the Differential Decay Curve Method. The trend of normalised B(E2) reveals a drop in correspondance of the 81+ state. This feature is also present in 122Ba: entering the backbending region the interplay between collective and quasiparticle degrees of freedom have to be carefully taken into account.

Products of 130Te + 275 MeV 64Ni and 208Pb + 345 MeV 58Ni collisions at energies slightly above the Coulomb barrier have been studied in two gamma spectroscopy thick target experiments. The product yield distributions have been established from the γ – γ coincidence analysis supplemented by target radioactivity measurements. Neutron evaporation from excited primary products has been estimated to determine the pre-emission maps of fragments. The transfer of protons and neutrons between the colliding ions is discussed in terms of the N / Z ratio equilibration. The discussion of experimental N / Z values compared with expectations based on potential energy minimizations leads to conclusion that the involved nuclei are dynamically deformed during the crucial interaction time. These results are discussed in connection with the earlier published study of the 208Pb + 350 MeV 64Ni system [1] . The present and perspective use of deep-inelastic reactions for spectroscopic studies of exotic neutron-rich nuclei in experiments with stable and radioactive beams is outlined.

The gyromagnetic factors of yrast states in {sup 156,158}Gd and {sup 166,168}Er, belonging to the ground-state rotational band, have been measured with the transient magnetic-field technique. Levels of interest were populated in charge exchange induced by a {sup 58}Ni beam. Mixed enriched isotope targets were employed in order to avoid systematic errors when comparing the results for the different isotopes. {sup 158}Gd and {sup 168}Er were used as internal calibration. In both {sup 156}Gd and {sup 166}Er significantly smaller reduction of the {ital g} factor with increasing spin has been found than previously reported, in agreement with the predictions of cranked-shell-model and cranked Hartree-Fock-Bogouliubov calculations.

Gyromagnetic ratios of the 2 1 + and 4 1 + states in 192,194,196 Pt and of the 2 2 + states in 192,194 Pt were simultaneously measured by the transient-field perturbed angular correlation method in Coulomb excitation using a multi-isotopic Pt target and thin polarized Fe and Gd foils as ferromagnetic hosts. The experimental g -factors were found identical within errors. These and previous existing data indicate the independence of the low-lying state g -factors in even stable Pt nuclei with respect to the spin and neutron number.

The magnetic moment of the 19/${2}^{\mathrm{\ensuremath{-}}}$ state in $^{39}\mathrm{K}$ has been measured by the transient field technique. The state was excited by the inverse reaction $^{12}\mathrm{C}$${(}^{32}$S,p\ensuremath{\alpha}${)}^{39}$K and the recoil nucleus traversed a thin Gd foil. Its absolute g factor, g=0.35(3), was obtained by an internal calibration, which makes use of the magnetic moment of the 15/${2}^{+}$ state in $^{41}\mathrm{Ca}$ also excited in the same reaction. A mean g factor for the states ${3}^{\mathrm{\ensuremath{-}}}$, ${5}^{\mathrm{\ensuremath{-}}}$ in $^{36}\mathrm{Ar}$, g=0.52(6), determined in a simultaneous measurement is consistent with the self-conjugate nature of the nucleus, giving further support to the validity of the field calibration. The experimental result agrees with shell-model predictions.

High-spin states in {sup 83}Rb were populated in the reaction {sup 11}B+{sup 76}Ge at beam energies of 45 and 50 MeV. {gamma} rays were detected with the spectrometer GASP. The level scheme of {sup 83}Rb was extended up to 13.9 MeV. Mean lifetimes of 23 levels were determined using the Doppler-shift-attenuation method. Among the bands newly established is a sequence comprising intense M1 transitions and crossover E2 transitions. This sequence turns out to be irregular and thus shows that magnetic rotation as observed in the neighboring odd-odd isotopes is not realized in this odd-even nuclide. Excited states in {sup 83}Rb were interpreted in terms of the shell model using the model space {pi}(0f{sub 5/2},1p{sub 3/2},1p{sub 1/2},0g{sub 9/2}) {nu}(1p{sub 1/2},0g{sub 9/2}). The configurations predicted for the negative-parity M1 sequence reproduce the M1 transition strengths fairly well.

The nuclei Y-85 and Y-86 (were studied in two series of experiments conducted by using the heavy-ion reactions Ge-76(N-14, 4n)Y-86 and Cr-52(Cl-37, 2pxn)Y-85,Y-86. The analysis of double and triple coincidences of gamma rays along with the investigation of angular distributions led to the extension of the level schemes of the Y-85 and Y-86 nuclei to spins and excitation energies higher than observed in previous experiments. In addition, a few new levels with low spins and excitation energies were identified in both nuclei. fit order to better understand the nuclear structure of these isotopes. shell-model calculations were carried out considering a valence space formed by the proton and neutron orbitals f5/2, p3/2, P1/2, and g9/2., This work was partially supported by the Romanian National Authority for Scientific Research under the contracts No. ID-117/2007 and ID-362/2007 and by the European Community FP6 under contract EURONS No. RII3-CT-2004-506065. The authors would like to thank G. Manente and M. Loriggiola of the Target Laboratory at the National Laboratory of Legnaro (INFN-LNL) for preparing the targets for both series of experiments. Many thanks are extended to the operating crews of the XTU and FN Tandem accelerators at INFN-Legnaro and NIPNE-Bucharest, respectively. C.R. also wishes to thank his wife, Gra¸tiela, for critically reviewing the manuscript and for her unceasing support.

The lifetimes of excited states of the 122Ba ground—state band, populated via the 108Cd(16O,2n)122Ba and the 112Sn(13C,2n)122Ba reactions, have been measured using the Recoil Distance Doppler—Shift method. The level scheme of 122Ba has also been revised.

The g -factor of the first 2 + states in three stable N =82 nuclei, 140 Ce, 142 Nd and 144 Sm, have been measured using the transient magnetic field technique. The levels under study were Coulomb excited with 110–116 MeV 32 S beams and spin precession after passing a thin polarized iron foil was measured. The field strength has been checked using the first 2 + state in 148 Sm as internal calibration. The obtained values were 0.97 (9), 0.84 (7), 0.76 (11) for 140 Ce, 142 Nd and 144 Sm, respectively. These remarkably lower values with respect to shell-model predictions in a proton subspace are explained in terms of neutron core excitation by quasiparticle random-phase-approximation calculations.

The rate of the hydrogen-burning carbon-nitrogen-oxygen (CNO) cycle is controlled by the slowest process, 14N(p,γ )15O, which proceeds by capture to the ground and several excited states in 15O. Previous extrapolations for the ground state contribution di

The feasibility of the entire process of γ -ray tracking is demonstrated experimentally for the first time. The accuracy of the results is verified by the capability to carry out a Doppler correction of γ -rays emitted in flight. The resolution of the 846.8 keV transition detected with the MARS detector after Coulomb excitation of a 56 Fe beam could be improved from approximately 16 up to 4.6 keV (FWHM). This result corresponds to an obtained position resolution of about 6 mm (FWHM).

The talk will be mainly devoted to the measurement of the cross section of the 3He(alpha,gamma)7Be reaction which belongs to the p-p chain. Actually, solar neutrino fluxes depend both on astrophysical and on nuclear physics inputs, namely on the cross sections of the reactions responsible for neutrino production inside the Solar core. While the flux of solar 8B neutrinos has been recently measured at Superkamiokande with a 3.5% uncertainty and a precise measurement of 7Be neutrino flux is foreseen in the next future, the predicted fluxes are still affected by larger errors. The largest nuclear physics uncertainty to determine the fluxes of 8B and 7Be neutrinos comes from the 3He(alpha,gamma)7Be reaction. The uncertainty on its S-factor is due to an average discrepancy in results obtained using two different experimental approaches: the detection of the delayed gamma rays from 7Be decay and the measurement of the prompt gamma emission. The LUNA Collaboration has performed a new high precision experiment with both techniques at the same time. Thanks to the low background conditions of the Gran Sasso LUNA accelerator facility, the cross section has been measured down to 93 keV, the lowest interaction energy ever reached. The S-factors from the two methods do not show any discrepancy within the experimental errors. An extrapolated S(0) = 0.560±0.017 keV barn is obtained. Moreover, branching ratios between the two prompt gamma -transitions have been measured with 3\u20138% accuracy. Recently, the LUNA Collaboration has presented to the Scientific Board of Gran Sasso Laboratory its experimental program for the next five years based on the existing 400 kV accelerator facility. A Letter of Intent addressing the possibility to install a 3 MV machine at Gran Sasso has also been submitted to the Board. The LUNA scientific programs with both the 400 kV and 3 MV accelerator facilities will be illustrated in the final part of the talk.

Theg-factor of the 7+ state in100Rh withT1/2=140(5) ns and of the 6− state in104Rh withT1/2=47(3)ns has been measured by the time-differential perturbedγ-ray angular distribution method (TDPAD). The obtained values are +0.67(2) and +0.33(1) respectively. The two nuclei were populated with reactions induced by7Li on96,100Mo at a bombarding energy of 30 MeV. Shell model calculations using effective single particle moments show that the 7+ state in100Rh has mostly a πg9/2 ⊗ vd5/2 configuration, while the main component of the 6− state in104Rh is the πg9/2 ⊗ vh11/2.

The g-factor of the first 2+ state in198Hg,200Hg and202Hg has been measured using the thin foil Transient Field technique. The values were calibrated to the known g-factor of the first 5/2− state in199Hg. The levels were Coulomb excited by 217 MeV nickel ions with gadolinium acting as ferromagnetic medium. The obtained values are rather constant and contradict a previously observed dip at200Hg. Two other g-factors have been remeasured in199Hg.

The g-factor of the octupole vibrational state 3− at 1810 keV in144Sm has been measured to be 0.76(9) by means of the transient field technique. The state has been Coulomb excited by 217 MeV58Ni beam. The obtained value agrees with the predictions of RPA calculations and confirms the dominance of the proton particle-hole configuration π(1h11/2−2d5/2−1)

Relative g-factor of the first 2+ and 4+ states have been measured with the transient field technique in156Gd and158Gd. The precession of gamma rays depopulating the levels under study were observed, after passing through thin polarized gadolinium. The observed values agree with the predictions of the rotational model, i.c. g(4+)= g(2+), while contrasting the hypothesis that in156Gd the g-factor of the 4+ is reduced with respect to the 2+, because of rotational alignment.

The electromagnetic decay properties of high-spin states in $^{52}\mathrm{Mn}$ have been studied through various experiments with the GASP and EUROBALL arrays plus the ISIS light charged-particle detector and the Neutron Wall. From \ensuremath{\gamma}-\ensuremath{\gamma} particles coincidence measurements, spins, and parities of these states and branching ratios of their decay \ensuremath{\gamma} rays have been determined. Using the Doppler-shift attenuation method the mean life of some states have been established. These results are compared with large-scale shell-model calculations in the full $\mathit{fp}$ shell.

Solar neutrino fluxes depend both on astrophysical and on nuclear physics inputs, namely on the cross sections of the reactions responsible for neutrino production inside the Solar core. While the flux of solar $^{8}\mathrm{B}$ neutrinos has been recently measured at Superkamiokande with a 3.5% uncertainty and a precise measurement of $^{7}\mathrm{Be}$ neutrino flux is foreseen in the next future, the predicted fluxes are still affected by larger errors. The largest nuclear physics uncertainty to determine the fluxes of $^{8}\mathrm{B}$ and $^{7}\mathrm{Be}$ neutrinos comes from the $^{3}\mathrm{He}$($\ensuremath{\alpha},\ensuremath{\gamma}$)$^{7}\mathrm{Be}$ reaction. The uncertainty on its S-factor is due to an average discrepancy in results obtained using two different experimental approaches: the detection of the delayed \ensuremath{\gamma} rays from $^{7}\mathrm{Be}$ decay and the measurement of the prompt \ensuremath{\gamma} emission. Here we report on a new high precision experiment performed with both techniques at the same time. Thanks to the low background conditions of the Gran Sasso LUNA accelerator facility, the cross section has been measured at ${E}_{\mathrm{c}.\mathrm{m}.}=170$, 106, and 93 keV, the latter being the lowest interaction energy ever reached. The S-factors from the two methods do not show any discrepancy within the experimental errors. An extrapolated $S(0)=0.560\ifmmode\pm\else\textpm\fi{}0.017$ keV barn is obtained. Moreover, branching ratios between the two prompt \ensuremath{\gamma}-transitions have been measured with 5--8% accuracy.

High-spin states in $^{35}\mathrm{Ar}$ and $^{35}\mathrm{Cl}$ have been populated in the $^{24}\mathrm{Mg}$($^{16}\mathrm{O}$, $\ensuremath{\alpha}n$) and $^{24}\mathrm{Mg}$($^{16}\mathrm{O}$, $\ensuremath{\alpha}p$) reactions, respectively, at a beam energy of 70 MeV. The comparison between the level schemes of these mirror nuclei shows a striking asymmetry in the population yield of high-spin analog states of positive parity, which indicates different intensities of $E1$ transitions connecting positive- and negative-parity structures in both nuclei. Large energy differences are observed between analog states of negative parity with configurations of dominant pure single-particle character. This results from the comparison with large-scale shell-model calculations in the ${s}_{1/2}{d}_{3/2}{f}_{7/2}{p}_{3/2}$ valence space. It is shown that important contributions to the energy differences arise from the multipole Coulomb and the relativistic electromagnetic spin-orbit interactions.

The flux of {sup 7}Be and {sup 8}B neutrinos from the Sun and the production of {sup 7}Li via primordial nucleosynthesis depend on the rate of the {sup 3}He({alpha},{gamma}){sup 7}Be reaction. In an extension of a previous study showing cross section data at 127-167 keV center-of-mass energy, the present work reports on a measurement of the {sup 3}He({alpha},{gamma}){sup 7}Be cross section at 106 keV performed at Italy's Gran Sasso underground laboratory by the activation method. This energy is closer to the solar Gamow energy than ever reached before. The result is {sigma}=0.567{+-}0.029{sub stat}{+-}0.016{sub syst} nb. The data are compared with previous activation studies at high energy, and a recommended S(0) value for all {sup 3}He({alpha},{gamma}){sup 7}Be activation studies, including the present work, is given.

High‐spin states in 168Tm were investigated by means of γ‐ray spectroscopy techniques using the GASP multidetector array. Rotational bands have been established and identified in terms of their configurations.

High-spin states in the neutron-deficient140Gd nucleus have been studied with the 92Mo(54Fe,alpha2p) reaction at a beam energy of 240 MeV. The level scheme of 140Gd was considerably extended from what was previously known. In this work we concentrate on one of the 9 bands observed, which presents relatively strong M1 transitions and negligible signature splitting, and has an isomeric band-head, indicating a strongly coupled or high-K configuration. We compare this band to the Kpi = 8- bands observed in N=74 isotones and propose a similar configuration assignment, but with a somewhat larger deformation.

The nuclear physics input from the 3He(alpha,gamma)7Be cross section is a major uncertainty in the fluxes of 7Be and 8B neutrinos from the Sun predicted by solar models and in the 7Li abundance obtained in big-bang nucleosynthesis calculations. The present work reports on a new precision experiment using the activation technique at energies directly relevant to big-bang nucleosynthesis. Previously such low energies had been reached experimentally only by the prompt-gamma technique and with inferior precision. Using a windowless gas target, high beam intensity, and low background gamma-counting facilities, the 3He(alpha,gamma)7Be cross section has been determined at 127, 148, and 169 keV center-of-mass energy with a total uncertainty of 4%. The sources of systematic uncertainty are discussed in detail. The present data can be used in big-bang nucleosynthesis calculations and to constrain the extrapolation of the 3He(alpha,gamma)7Be astrophysical S factor to solar energies.

The yrast level structure of {sup 216}Rn has been studied using in-beam spectroscopy {alpha}-{gamma}-{gamma} coincidence techniques through the {sup 208}Pb({sup 18}O, 2{alpha}2n) reaction in the 91-93 MeV energy range, using the 8{pi} GASP-ISIS spectrometer at Legnaro. The level scheme of {sup 216}Rn resulting from this study shows alternating parity bands only above a certain excitation energy. From this result, the lightest nucleus showing evidence of octupole collectivity at low spins is still {sup 216}Fr, thereby defining the lowest-mass corner for this kind of phenomenon as N{>=}129 and Z{>=}87.

The nucleus $^{31}\mathrm{P}$ has been studied in the $^{24}\mathrm{Mg}$($^{16}\mathrm{O}$,2$\ensuremath{\alpha}p$) reaction with a 70-MeV $^{16}\mathrm{O}$ beam. A complex level scheme extended up to spins 17/2${}^{+}$ and 15/2${}^{\ensuremath{-}}$, on positive and negative parity, respectively, has been established. Lifetimes for the new states have been investigated by the Doppler shift attenuation method. Two shell-model calculations have been performed to describe the experimental data, one by using the code ANTOINE in a valence space restricted to the sd shell, and the other by applying the Monte Carlo shell model in a valence space including the $\mathit{sd}\text{\ensuremath{-}}\mathit{fp}$ shells. The latter calculation indicates that intruder excitations, involving the promotion of a $T=0$ proton-neutron pair to the fp shell, play a dominant role in the structure of the positive-parity high-spin states of $^{31}\mathrm{P}$.

Angular distributions and angular correlations have been measured for the emission of one and two \ensuremath{\alpha}-particles in the $^{18}\mathrm{O}+^{207,208}\mathrm{Pb}$,$^{209}\mathrm{Bi}$ reactions at several beam energies above the Coulomb barrier. The results rule out fusion evaporation as the main reaction mechanism for the channels involving \ensuremath{\alpha}-particle emission and support the interpretation of the breakup of the $^{18}\mathrm{O}$ projectiles into at least $^{14}\mathrm{C}$+\ensuremath{\alpha} and $^{10}\mathrm{Be}+^{8}\mathrm{Be}$ before fusion.

In stars, four hydrogen nuclei are converted into a helium nucleus by two competing nuclear fusion processes: the proton ‐ proton chain (p‐p) and the carbon ‐ nitrogen ‐ oxygen (CNO) cycle. At temperatures higher than 2×107 K, the CNO cycle dominates the energy production. In particular, its rate is determined by the slowest reaction: 14N(p,γ)15O. Direct measurement in a laboratory at the surface of the Earth is hampered by the background due to the cosmic rays. Here we report on an experiment performed with the LUNA (Laboratory for Underground Nuclear Astrophysics) accelerator placed deep underground in the INFN Gran Sasso laboratory (Italy). Thanks to the cosmic ray suppression provided by the mountain shield, we could measure the 14N(p,γ)15O cross section for the first time directly at energies corresponding to stellar temperatures and with unpreceedent accuracy. In particular we used a large solid angle BGO detector with a differentially pumped windowless gas target. The lowest measured energy is 70.1 keV. Our results have important consequences for the formation of carbon stars, for an independent lower limit on the age of the universe, and for solar neutrino flux.

Spectroscopic quadrupole moment measurements for high‐spin isomeric states in 192,193,194Pb nuclei have been performed by the time‐differential perturbed γ‐ray angular distribution method. The quadrupole moments of the isomers described by quasineutron configurations in neutron‐deficient Pb nuclei are well reproduced by the pairing plus quadrupole model, which predicts for these states a very small prolate deformation β2 ≈0.02. The quadrupole moment of the 11− isomeric state in 192Pb involving the π(3s1/2−2 1h9/2 1i13/2) configuration corresponds to a deformation β2=−0.11(1). The quadrupole moments of the proton intruder states in Pb nuclei are compared with theoretical predictions of tilted‐axis cranking, mean‐field and interacting boson models.

International audience; Measurements of the excitation energies of superdeformed states via the observation of single-step linking transitions have now been made in three even-A Pb nuclei, with a quasicontinuum analysis providing a limit in a fourth, odd-A case. These results allow us to take the first steps towards establishing systematic trends in excitation energies and binding energies in the second minimum in Pb isotopes

The ridge structure with ΔEγ=±30 keV, recently observed in the reaction 187 MeV 37Cl+120Sn and attributed to a hyperdeformed nuclear shape, has been confirmed in a new proton-γ coincidence experiment and assigned to the 152Dy nucleus. Estimates of the cross section for the population of the 30 keV ridge and for the associated entry states have been obtained. The proton spectra in coincidence with γ rays of different Dy isotopes show effects related to the exit channel and to the angular momentum but they are scarcely sensitive to the selection of different shapes (oblate, normal deformed prolate, superdeformed) in the same residual nucleus 152Dy. The energy of the protons in coincidence with the ΔEγ=±30 keV ridge is however larger than expected. This effect is discussed in the framework of the fission-evaporation competition.

The hyperdeformed ridge structure recently observed in the reaction of 187 MeV Cl-37 on Sn-120 has been confirmed in a new proton-gamma coincidence experiment at the GASP spectrometer and assigned to the nucleus Dy-152. Proton spectra have been measured in coincidence with gamma-rays belongings to the different structures in Dy-152 (oblate, prolate, super- and hyper-deformed). The deformation of the final evaporation residue affects only weakly the proton evaporation from the compound nucleus. Evidence has been found that the energy of the protons in coincidence with the hyperdeformed structure is larger than expected. This effect is discussed in the framework of the fission-evaporation competition.

The excitation energy of the lowest-energy superdeformed band in Pb-196 is established using the techniques of time-correlated gamma-ray spectroscopy. Together with previous measurements on Pb-192 and Pb-194, this result allows superdeformed excitation energies, binding energies, and two-proton and two-neutron separation energies to be studied systematically, providing stringent tests for current nuclear models. The results are examined for evidence of a "superdeformed shell gap."

The mean lifetimes of the ${25/2}^{+}$, ${21/2}^{+}$, and ${17/2}^{+}$ states in the highly deformed (HD) band of $^{133}\mathrm{Nd}$, excited via the reaction $^{104}\mathrm{Pd}$($^{32}\mathrm{S}$,2$\mathit{pn}$)$^{133}\mathrm{Nd}$, have been measured using a recoil distance Doppler-shift method. The decay out of the HD band occurs as a result of an admixture of normally deformed (ND) components into the HD states' wave function. The consistency in the mixing amplitude was assessed from the measured lifetimes, branching ratios, and quadrupole moments of the HD and the ND bands. This analysis unequivocally confirms the earlier approach to explain the decay-out mechanism.