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We performed a proton‐capture reaction on 92Mo at energies relevant for the p process. The reaction was investigated by the in‐beam technique using the γ‐ray detector array HORUS (High efficient Observatory for γ‐Ray Unique Sectroscopy) at the TANDEM ion accelerator of the University of Cologne.

In our recent study of the isotope shifts of Kr isotopes near rp‐process path in the framework of the RMF theory, we have found that due to large shell gaps in the deformed space, several N = Z nuclei exhibit the double magicity of protons and neutrons. These nuclei are known to contribute to large abundances in the rp‐process nucleosynthesis and have been shown to be the waiting‐point nuclei. In another study of the shell effects at N = 126 near the neutron drip line, we have found that nuclei exhibit additional stability beyond the neutron drip line.

The macroscopic collective Lagrangian is determined by microscopic time‐dependent density functional calculations. Consequently, reduced mass, friction coefficient, and nucleus‐nucleus potential are extracted by means of spline interpolation function.

States that exhibit the properties of α‐cluster resonances are studied in (2s‐1d)‐shell nucleus 32S. The generalized Hamiltonian of the Elliott SU(3) model is used to classify these states and to calculate their spectra. The results of the analysis are found to be in a good agreement with the bulk of the experimental data.

In this work we present new data for the sub‐barrier fusion of the system 6He+206Pb obtained in the Centre de Recherches du Cyclotron (UCL), in Louvain‐la‐Neuve, Belgium. The preliminary results suggest the absence of fusion enhancement at sub‐barrier energies.

By applying the Hartree‐Fock calculations with the newly developed methods and interactions, spherical shell structure of medium‐mass nuclei is investigated, with paying special attention to the magicity.

Characteristic conditions that should be met for two‐quasiparticle chiral bands to reach degeneracy were examined using two‐quasiparticle‐plus‐triaxial‐rotor model for the A∼100, 130 and 190 mass regions. These results suggest that degeneracy in two‐quasiparticle chiral bands can be reached only for restricted particle‐hole configurations, for which the particle (hole) occupy the lowest (highest) energy orbitals in the high‐j shell, and for which the individual angular momenta are strictly mutual perpendicular.

We investigate the heavy‐element nucleosynthesis of a massive star whose mass in the main sequence stage is Mms = 70 M⊙. Detailed calculations of the nucleosynthesis are performed during the hydrostatic stellar evolution until the core composed of iron‐group nuclei begins to collapse. As a supernova explosion model, a collapsar model is constructed whose jets are driven by magnetohydrodynamical effects of a differentially rotating core. The heavy‐element nucleosynthesis inside the jet of a collapsar model is followed along the trajectories of stream lines of the jet. We combine the results of both hydrostatic and heavy‐element nucleosyntheses to compare with the solar abundances. We find that neutron‐rich elements of 70

Electron capture reactions on Ni and Co isotopes are investigated by shell model calculations in steller environments. The capture rates depend sensitively on the distribution of the Gamow‐Teller (GT) strength. The capture rates obtained by using GXPF1J Hamiltonian for fp‐shell are found to be consistent with the rates obtained from experimental GT strength in 58Ni and 60Ni. Capture rates in Co isotopes, where there were large discrepancies among previous calculations, are also investigated. Beta decays of the N = 126 isotones are studied by shell model calculations taking into account both the GT and first‐forbidden (FF) transitions. The FF transitions are found to be important to reduce the half‐lives by twice to several times of those by the GT contributions only. Implications of the short half‐lives of the waiting point nuclei on the r‐process nucleosynthesis are discussed for various astrophysical conditions.

The question of phases and phase‐transitions of cluster states is reviewed. First some features of the algebraic models are recalled. Then we address the question, what the experimental spectrum of 20Ne suggests on the phase of the 16O+α system.

A Recoil‐Beta Tagging (RBT) experiment was recently performed at the accelerator laboratory at the University of Jyvaskyla in order to identify T = 1 excited states in the medium‐heavy N = Z = 33 nucleus 66As. The fusion‐evaporation reaction 28Si(40Ca,pn)66As was employed at a beam energy of 75 MeV. The experiment was carried out utilising the JUROGAM II γ‐ray spectrometer in conjunction with the gas‐filled recoil separator RITU and the GREAT focal plane spectrometer system. The half‐lives and ordering of the two known isomeric states in 66As have been determined. In addition, several new prompt γ‐ray transitions from excited states both bypassing and decaying to the isomeric states in 66As have been observed.

We investigate the possibility of the r‐process during the magnetohydrodynamical (MHD) explosion of supernova in a massive star of 13 M⊙ with the effects of neutrinos included. Contrary to the case of the spherical explosion, jet‐like explosion due to the combined effects of rotation and magnetic field lowers the electron fraction significantly inside the layers. We find that the ejected material of low electron fraction responsible for the r‐process comes out from the inner deep region of the core that is made up of iron‐group nuclei. This leads to the production of the second to third peak in the solar r‐process elements. We suggest that there are some variations in the r‐process nucleosynthesis according to the initial conditions of rotational and magnetic fields.

Spectroscopic studies of nuclei in the A∼250, Z∼100 region provide critical input to theoretical models that attempt to describe the structure and stability of the heaviest elements. We report here on new spectroscopic studies in the N = 150,151 nuclei 244,245Pu. (Z = 94). Excitations in these nuclei on the neutron‐rich side of the valley of stability, accessed via inelastic and transfer reactions, complement fusion‐evaporation studies of Z≥100 nuclei. States in 244,245Pu were populated using 47Ti and 208Pb beams incident on a 244Pu target, with delayed and prompt gamma rays detected by the Gammasphere array. The new results are discussed in the context of emerging systematics of one‐ and two‐quasiparticle excitations in N≥150 nuclei.

The 18O(p,α)15N reaction is of great importance in several astrophysical scenarios, as it influences the production of key isotopes such as 19F, 18O and 15N. In this work, a high accuracy 18O(p,α)15N reaction rate is proposed, based on the simultaneous fit of direct measurements and of the results of a new Trojan Horse experiment. In particular, we have focused on the study of the broad 660 keV 1/2+ resonance. Since Γ∼100–300 keV, it strongly influences the nearly‐zero‐energy region of the cross section by means of the low‐energy tail of the resonant contribution and dominates the cross section at higher energies. Here we provide a factor of 2 larger reaction rate above T∼0.5 109 K based over our new improved determination of its resonance parameters.

Spectra of two‐step γ cascades (TSCs) following the neutron capture in 159Tb were measured by the sum‐coincidence technique with a two‐HPGe‐detector facility [1] installed at a pure sub‐thermal neutron beam of the 15 MW light‐water research reactor at Řež near Prague. In order to obtain information about the quantities governing the γ decay of 160Tb levels—the photon strength functions (PSFs) and the level density (LD)—experimental TSC spectra were compared with the output of simulations of the γ cascade decay based on the validity of extreme statistical model. These simulations were performed with the aid of the DICEBOX algorithm [2] assuming various combinations of the PSFs and LD. The results obtained lead to an inescapable conclusion that the Scissors Mode (SM) plays a crucial role in the cascade γ decay of the product nucleus 160Tb. This finding represents the first evidence for the existence of the SM in an odd‐odd nucleus.

High spin states in 194Tl, excited through the 181Ta(18O,5n) fusion evaporation reaction, were studied using the AFRODITE array at iThemba LABS. Candidate chiral bands built on the πh9/2⊗νi13/21 configuration were found. Furthermore these bands were observed through a band crossing caused by the excitation of a νi13/2 pair. Above the band crossing the excitation energies remain close, suggesting that chirality may persist for the four quasiparticle configuration too.

We used the equations of state (EoS) of dense nuclear matter to construct the macroscopic properties of neutron stars and test them using available observational results. The Dirac‐Brueckner‐Hartree‐Fock mean field calculations approximated by their parameterized form are the basis of our calculations for the star interior. We calculated the central pressure, density, radius and mass both without and with allowance for hyperons, and compared these results with astronomical observations.

Photoneutron cross sections for 90Zr near neutron threshold were examined with a photon difference technique using laser Compton scattering γ‐ray beams. The cross section decreasing in the vicinity of neutron threshold exhibited a steep rise within 150 keV above the threshold. We draw attention to a possible relation of this striking behavior to the 3P valence neutron resonance known in neutron capture in the mass region A≈90.

We report on the status of a new evaluation of the rates in astrophysical conditions of 19 capture and 15 transfer reactions on stable targets with mass numbers A

The X(5) symmetry describes nuclei at the critical point of the shape phase transition from axially deformed rotor nuclei to spherical vibrators. 150Nd, 152Sm, and 154Gd were the first nuclei where the predicted charateristics of the X(5) symmetry were observed. Later it was shown that also 176,178,180Os can be successfully described with the X(5) symmetry.In the close vicinity of shape phase transitions one expects strongly changing nuclear shapes. In the X(5) region around A = 150 this was observed for nuclei with different neutron numbers, whereas in the X(5) region around A = 180 this is to be expected for different proton numbers. The aim of the work presented here is the confirmation of a rapid shape change for nuclei close to 178Os. Besides the knowledge on the level scheme of the nuclei of interest, especially absolute E2 transition strengths are crucial for the interpretation of nuclear structure. Prolate deformation is expected for 176W. Thus we performed a recoil distance Doppler shift (RDDS) m...

New fusion data for the {sup 4}He+{sup 64}Zn system at sub-barrier energies are measured to cover the same energy region of previous measurements for {sup 6}He+{sup 64}Zn. Aim of the experiment was to compare the fusion excitation functions for the two system to investigate on the effects of the {sup 6}He neutron-halo structure on the fusion reaction mechanism at energies around the Coulomb barrier. The fusion cross section was measured by using an activation technique. Comparing the two systems, we observe an enhancement of the fusion cross section in the reaction induced by {sup 6}He, at and below the Coulomb barrier.

The stable Cd isotopes have long been used as paradigms for spherical vibrational motion. Extensive investigations with in‐beam γ spectroscopy have resulted in very‐well‐established level schemes, including many lifetimes or lifetime limits. A programme has been initiated to complement these studies with very‐high‐statistics β decay using the 8π spectrometer at the TRIUMF radioactive beam facility. The decays of 112In and 112Ag have been studied with an emphasis on the observation of, or the placement of stringent limits on, low‐energy branches between potential multi‐phonon levels. A lack of suitable 0+ or 2+ three‐phonon candidates has been revealed. Further, the sum of the B(E2) strength from spin 0+ and 2+ states up to 3 MeV in excitation energy to the assigned two‐phonon levels falls far short of the harmonic‐vibrational expectations. This lack of strength points to the failing of collective models based on vibrational phonon structures.

Elastic‐scattering angular distributions for the 6Li+64Zn system were measured at energies from below to above the Coulomb barrier. The experimental data were analyzed within the optical model to study the energy dependence of the interaction potential. The results suggest the presence of the breakup threshold anomaly. Preliminary results on the fusion cross‐sections for the same system are also reported.

Large scale mean field calculations from proton to neutron drip lines have been performed using the Hartree‐Fock‐Bogoliubov method based on the Gogny nucleon‐nucleon effective interaction. This extensive study has shown the ability of the method to reproduce bulk nuclear structure data available experimentally. This includes nuclear masses, radii, matter densities, deformations, moment of inertia as well as collective mode (low energy and giant resonances). In particular, the first mass table based on a Gogny‐Hartree‐Fock‐Bogolyubov calculation including an explicit and coherent account of all the quadrupole correlation energies is presented. The rms deviation with respect to essentially all the available mass data is 798 keV. Nearly 8000 nuclei have been studied under the axial symmetry hypothesis and going beyond the mean‐field approach.

The rapid neutron‐capture process, or r‐process, is known to be of fundamental importance for explaining the origin of approximately half of the A>60 stable nuclei observed in nature. In recent years nuclear astrophysicists have developed more and more sophisticated r‐process models, eagerly trying to add new astrophysical or nuclear physics ingredients to explain the solar system composition in a satisfactory way.We show here that the decompression of the neutron star matter may provide suitable conditions for a robust r‐processing. After decompression, the inner crust material gives rise to an abundance distribution for A>130 nuclei similar to the one observed in the solar system. Similarly, the outer crust if heated at a temperature of about 8 109 K before decompression is made of exotic neutron‐rich nuclei with a mass distribution close to the 80≤A≤130 solar one. During the decompression, the free neutrons (initially liberated by the high temperatures) are re‐captured leading to a final pattern simila...

We study electroweak processes in complex nuclei within the framework of self‐consistent mean field theories including pairing and RPA correlations. We review the adiabatic time dependent Hartree‐Fock (HF) theory and its ability to simultaneously handle large and small amplitude modes. We apply the formalism to the study of single and double beta decay as normal modes of the system, allowing for collective deformation, using Skyrme density‐dependent two‐body interactions. We also apply the formalism to the study of parity‐violating electron scattering. We highlight nuclear structure issues that are crucial for the correct analysis of these processes, namely neutron densities and spectroscopic factors, whose proper knowledge and interpretation in stable nuclei is required to get reliable predictions on exotic nuclei.

The interplay of isospin asymmetry and finite temperature in nuclei plays an important role on properties of nuclear excitations and weak interaction rates in stellar environment. Recently a fully self‐consistent microscopic framework, based on Hartree‐Fock plus random phase approximation using Skyrme functionals, has been introduced for description of excitations and weak‐interaction cross sections at finite temperature. Another self‐consistent framework involving nuclei at finite temperature has also been developed within relativistic mean field theory using effective Lagrangians with density dependent meson‐nucleon vertex functions. Nuclear excitations are studied using finite temperature random phase approximation for the range of temperatures T = 0–2 MeV, as well as in nuclei far from stability. In the focus of research are the structure properties of exotic modes of excitation (e.g. pygmy dipole resonances) and charge‐exchange modes (e.g. Gamow‐Teller resonances and forbidden transitions). It is sho...

High spin states in 196Hg have been populated in the 198Pt(α,6n) reaction at 65 MeV and the level scheme has been extended. A new dipole band has been observed and a previously observed dipole has been confirmed. Excitation energies, spins and parities of these bands were determined from DCO ratio and linear polarization measurements. Possible quasiparticle excitations responsible for these structures are discussed.

Electron screening enhances cross sections for nuclear reactions at low energies. We have studied the 1H(7Li,α)4He reaction in inverse kinematics and observed large electron screening only when the metallic targets were under tensile stress. Hydrogen was loaded into Pd and PdAg alloy foils from gas phase and concentrations reached about 0.6 protons per metallic atom. Mechanical pressure creates stress induced states in the metal. Without pressure hydrogen occupies octahedral interstitial positions in the fcc Pd lattice. Under stress some protons move to dislocated octahedral (dis‐O) sites in the lattice. We believe that the magnitude of screening in various metals depends on the electron density on dis‐O sites in case of fcc lattices or dislocated tetrahedral sites in bcc metals. We are currently trying to confirm the above by determining the electron density at the sites occupied by protons via the measurement of proton Knight’s shift with 1H nuclear magnetic resonance technique.

In this work we have studied the break‐up of 12C following the reactions 10B(3He,pααα) and 11B(3He,dααα). The study was performed at the 5 MV tandem in Madrid. The break‐up gives us information on excited states in 12C from the famous Hoyle state up to an energy of almost 18 MeV. Using a highly segmented experimental set‐up the simultaneous detection of the three alpha particles in coincidence with a proton or deuteron respectively made possible a full kinematic reconstruction of the break‐up. On the basis of the energies of the 3 α particles and their angular correlations it has been possible to determine the spin and parity of states for cases in which the assignment has been doubtful. Some of these levels will also de‐excite via electromagnetic emission. The comparison between the energy of proton that populate a state of 12C and the sum of the energies of the 3α emitted from the same state makes possible to determine the presence of electromagnetic disintegration (γ) to lower states within 12C followed by the 3α break‐up.

Continuum Random Phase Approximation (CRPA) for relativistic point coupling models with density dependent coupling constants is applied to investigate collective excitations in spherical nuclei. In particular we study the impact of the exact continuum on the Giant Dipole Resonance of several Tin isotopes as well as the nuclear (γ,n) reaction rates which are important in astrophysical calculations.

Probing shell structure at a large neutron excess has been of particular interest in recent times. Neutron‐rich nuclei between the proton shell closures Z = 20 and Z = 28 offer an exotic testing ground for shell evolution. The development of the N = 40 gap between neutron fp and lg9/2 shells gives rise to highly interesting variations of collectivity for nuclei in this region. While 68Ni shows doubly magic properties in level energies and transition strengths, this was not observed in neighbouring nuclei. Especially neutron‐rich Fe isotopes proved particularly resistant to calculational approaches using the canonical valence space (fpg) resulting in important deviations of the predicted collectivity. Only an inclusion of the d5/2‐orbital could solve the problem [1]. Hitherto no transition strengths for 66Fe have been reported. We determined B(E2,21+→01+) values from lifetimes measured with the recoil distance Doppler‐shift method using the Cologne plunger for radioactive beams at National Superconducting ...

Reduced uncertainty in the thermonuclear rate of the {sup 33}S(p,{gamma}){sup 34}Cl reaction would help to improve our understanding of nucleosynthesis in classical nova explosions. At present, models are generally in concordance with observations that nuclei up to roughly the calcium region may be produced in these explosive phenomena; better knowledge of this rate would help with the quantitative interpretation of nova observations over the S-Ca mass region, and contribute towards the firm establishment of a nucleosynthetic endpoint. As well, models find that the ejecta of nova explosions on massive oxygen-neon white dwarfs may contain as much as 150 times the solar abundance of {sup 33}S. This characteristic isotopic signature of a nova explosion could possibly be observed through the analysis of microscopic grains formed in the environment surrounding a nova and later embedded within primitive meteorites. An improved {sup 33}S(p,{gamma}){sup 34}Cl rate (the principal destruction mechanism for {sup 33}S in novae) would help to ensure a robust model prediction for the amount of {sup 33}S that may be produced. Finally, constraining this rate could confirm or rule out the decay of an isomeric state of {sup 34}Cl(E{sub x} = 146 keV, t{sub 1/2} = 32 m) as a source formore » observable gamma-rays from novae. We have performed several complementary experiments dedicated to improving our knowledge of the {sup 33}S(p,{gamma}){sup 34}Cl rate, using both indirect methods (measurement of the {sup 34}S({sup 3}He,t){sup 34}Cl and {sup 33}S({sup 3}He,d){sup 34}Cl reactions with the Munich Q3D spectrograph) and direct methods (in normal kinematics at CENPA, University of Washington, and in inverse kinematics with the DRAGON recoil mass separator at TRIUMF). Our results will be used with nova models to facilitate comparisons of model predictions with present and future nova observables.« less

Photoneutron cross sections were measured for Au in the entire energy range of the (γ,n) channel based on a direct neutron‐counting technique with quasimonochromatic γ rays produced in inverse Compton‐scattering of laser photons with relativistic electrons. We present results of the measurement in comparison with the past data.

Photoneutron cross sections were measured for 108Pd, 106Pd, and 105Pd with laser‐Compton scattering γ‐ray beams in an application of the γSF method to a radioactive nucleus 107Pd. We present radiative neutron cross sections for 107Pd[6.5×106 y] obtained with the γSF method.

I report present status and perspectives of RIBF “RI Beam Factory (RIBF)” at RIKEN. RIBF is a top world‐class in‐flight RIB facility. Emphasis is given to on‐going and future programs at the new facility through introducing experimental devices and recent highlights.

The interrelation of the largely elongated nuclear shapes and clusterization is discussed by applying semimicroscopic methods. 36Ar is considered as a specific example, where recent experimental heavy‐ion scattering data seem to justify the theoretical predictions on the hyperdeformed states. Alpha‐emitting reactions are also suggested for its population.

We present computations of nucleosynthesis in low‐mass asymptotic‐giant‐branch stars of solar metallicity experiencing deep mixing. In this framework, we discuss the effects of recent improvements in relevant reaction rates for proton captures on intermediate‐mass nuclei. The calculations are then performed on the basis of a parameterized circulation, where the effects of the new nuclear inputs are best compared to previous works. We find that especially the new reaction rate for the 14N(p,γ)15O reaction implies considerable modifications in the composition of low mass red giant stars.

For the first time, the excited states in the extremely neutron‐deficient nucleus 180Pb have been observed in an in‐beam γ‐ray measurement employing the recoil‐decay tagging technique. Deduced level energies follow the trend of prolate intruder band level energies derived from heavier lead isotopes and reflect the persistence of magicity of the closed Z = 82 proton shell when approaching the proton drip line.

We examine explosive nucleosynthesis of p‐nuclei during a delayed neutrino‐driven, aspherical supernova explosion aided by standing accretion shock instability, based on two‐dimensional hydrodynamic simulations of the explosion of a 15M⊙ star. We find that p‐nuclei are mainly produced through γ‐processes, and that the nuclei lighter than 92Mo are abundantly synthesized in slightly neutron‐rich bubbles with electron fractions of Ye≤0.48. 94Mo, 96Ru, and 98Ru, are underproduced compared with the solar system, as in the spherical model.

The compression-mode isoscalar giant monopole resonance (ISGMR) has been studied in the Sn, Cd and Pb isotopes using inelastic scattering of 400 MeV {alpha}-particles at extreme forward angles, including 0 deg. We have obtained completely 'background-free' inelastic-scattering spectra for the Sn, Cd, and Pb isotopes for a wide angular and excitation-energy range. The various giant resonances excited with different transferred angular momenta were extracted by a multipole-decomposition analysis (MDA). It was found that the centroid energies of the ISGMR in Sn isotopes are significantly lower than the theoretical predictions. The K{sub {tau}} in the empirical expression for the nuclear incompressibility has been determined to be K{sub {tau}} = -550{+-}100 MeV for the Sn isotopes. The extracted value for the Cd isotopes is K{sub {tau}} = -480{+-}100 MeV. These numbers are consistent with values of K{sub {tau}} = -370{+-}120 MeV obtained from an analysis of the isotopic transport ratios in medium-energy heavy-ion reactions, K{sub {tau}} -500{sub -100}{sup +120} MeV obtained from constraints placed by neutron-skin data from anti-protonic atoms across the mass table, and K{sub {tau}} = -500{+-}50 MeV obtained from theoretical calculations using different Skyrme interactions and relativistic mean field (RMF) Lagrangians. Stringent constraints on interactions employed in nuclear structuremore » calculations are obtained on the basis of the experimentally determined values for K{sub {infinity}} and K{sub {tau}}. These parameters constrain as well the equation of state (EOS) of nuclear matter. However, a significant discrepancy still remains. The ISGMR positions in Sn and Cd isotopes are systematically lower than the predictions obtained on basis of determined from the ISGMR in {sup 208}Pb. This raises the question ''Why are Sn and Cd nuclei so soft?''. For a clue to solve the problem, we discuss the preliminary results on the exact positions of the ISGMR in {sup 204,206,208}Pb.« less

Weak interaction rates under stellar density and temperature conditions relevant for the rp process are studied in neutron‐deficient Kr isotopes. The nuclear structure part of the problem is described within the deformed Skyrme Hartree‐Fock+BCS+QRPA, which reproduces not only the beta‐decay half‐lives but also the available Gamow‐Teller strength distributions, measured under terrestrial conditions. The various sensitivities of the decay rates to both density and temperature are discussed. In particular, we study the contributions coming from excited states in the parent nucleus, which are thermally populated, and the competition between beta‐decays and continuum electron captures., This work was supported by Ministerio de Ciencia e Innovación (Spain) under Contract No. FIS2008–01301.

Structure of neutron-rich calcium isotopes are studied by shell model calculations with the inclusion of three-body interactions. The three-body force induces repulsive contributions to the monopole terms of the valence neutron-neutron interaction Ground state energies of the isotopes, which have deviations from the experimental values near drip-lines only with the microscopic two-body interaction, are found to be well reproduced up to the observed ones when the three-body interaction is included. The excitation energies of the 2{sub 1}{sup +} state in {sup 48}Ca and {sup 54}Ca are found to be enhanced with the inclusion of the three-body interaction. The three-body force thus plays a key role for the magicity of {sup 48}Ca and {sup 54}Ca. The magnetic dipole (M1) strength in {sup 48}Ca, which is fragmented in case with the microscopic two-body interaction only, is found to be concentrated and pushed up to higher excitation energy when the three-body interarction is included. An important role of the multipole components is pointed out for the concentration of the strength.

The proton‐induced pre‐equilibrium process in the energy range of 100 to 160 MeV, which leads to emission of composite ejectiles such as 3He and α‐particles, is discussed. New cross section and analyzing power measurements for the (p,3He) reaction on 93Nb at an incident energy of 160 MeV are presented, and these are found to be in agreement with the prediction of a statistical multistep theoretical formulation. The observed quenching of the analyzing power is also reproduced well by the theory. The results are consistent with earlier work at lower incident energies and other nuclear species.

The proton‐rich nucleus 33Ar has been produced at the low‐energy facility SPIRAL at GANIL. Spectroscopic studies of gamma and p emission of this nucleus were performed with the “Silicon Cube” detection system. The analysis of proton and gamma singles and coincidence spectra allowed us to establish a complete decay scheme of this nucleus. The comparison of the Gamow‐Teller strength distribution deduced from our experiment and the theoretical one obtained with the Shell Model permitted the determination of a quenching factor for the Gamow‐Teller strength.

Fission properties of proton‐induced fission on 232Th, 237Np, 238U, 239Pu and 241Am targets, measured at the Louvain‐la‐Neuve cyclotron facility at proton energies of 26.5 and 62.9 MeV, are compared with the predictions of the state‐of‐the‐art nuclear reaction code TALYS. The sensitivity of the calculations to the input parameters of the code and possible improvements are discussed.

A study of light neutron‐rich nuclei has been performed at the INFN‐LNS laboratory in Catania (Italy) by the (18O, 16O) reaction at 84 MeV incident energy on 9Be, 11B and 13C targets. The 16O ejectiles have been momentum analyzed and detected at forward angles by the MAGNEX magnetic spectrometer. The energy spectra of 15C show several known low lying states up to about 7 MeV excitation energy and unknown resonant structures at higher excitation energy. The strong excitation of these latter together with the measured width of about 2 MeV FWHM could indicate the presence of collective modes of excitation connected to the transfer of a correlated neutron pair. Also considerations regarding the reaction mechanism and the nuclei involved in the transfer seem to confirm such a conclusion. Similar features characterize the energy spectra of the 11Be and 13B nuclei. The achieved mass resolution (about 1/160) guarantying the identification of the reaction products corresponding to different reaction channels has a...