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We review the latest efforts devoted to the global prediction of atomic masses. Special attention is paid to the new developments made within the Hartree-Fock-Bogolyubov framework. So far, 9 HFB mass tables based on different parametrizations of the effective interactions in the Hartree-Fock and pairing channels have been published. We analyze their ability to reproduce experimental masses as well as nuclear-matter and giant-resonance properties. The possibility to derive within the HFB framework a universal effective interaction that can describe all known properties of the nuclei (including their masses) and of asymmetric nuclear matter is critically discussed. [ABSTRACT FROM AUTHOR]

Neutral atoms trapped with modern laser cooling techniques offer the promise of improving several broad classes of weak interaction experiments with radioactive isotopes. For nuclear β decay, demonstrated trap techniques include neutrino momentum measurements from beta-recoil coincidences, along with methods to produce highly polarized samples. These techniques enable experiments to search for non-Standard Model interactions, test whether parity symmetry is maximally violated, search for 2nd-class tensor and other tensor interactions, and search for new sources of time reversal violation. Ongoing efforts at TRIUMF, Berkeley, and Los Alamos will be highlighted. Trap experiments involving fundamental symmetries in atomic physics, such as time-reversal violating electric dipole moments and neutral current weak interactions, will be briefly mentioned. [ABSTRACT FROM AUTHOR]

In this talk a summary of the program and scientiffc highlights of the ENAM2004 conference will be presented. [ABSTRACT FROM AUTHOR]

Spallation reactions are considered an optimum neutron source for nuclear waste transmutation in accelerator-driven systems (ADS). They are also used to produce intense radioactive nuclear beams in ISOL facilities. A difficulty in both applications is the characterisation of these reactions in terms of residual nuclei production. In this paper we review the GSI experimental program for the investigation of spallation reactions and their implications both in radioactive nuclear beams production and basic nuclear structure research. [ABSTRACT FROM AUTHOR]

A double superconducting solenoid system is being installed at the Pelletron Laboratory of the University of São Paulo, Brazil. This system allows the production of secondary beams of light exotic nuclei like 8Li, 6He and others. The first results using this facility are presented. [ABSTRACT FROM AUTHOR]

The ISOLDE online mass separator located at CERN provides a large variety of radioactive ion beams for research on nuclear physics, nuclear astrophysics, fundamental interactions, atomic physics, radiochemistry, nuclear medicine, condensed matter science, life sciences and others. The recently operational REX-ISOLDE post-accelerator is capable of accelerating the isotopes produced at ISOLDE to energies of up to 3.0MeV/u by using an ion trap and charge breeder and a compact linear accelerator structure. The post-accelerator is complemented by a highly segmented Ge array in conjunction with a compact silicon strip detector at one of the secondary target positions, while a general spectroscopy setup occupies a second station. REX-ISOLDE has opened up the possibility of nuclear spectroscopy studies by means of transfer reactions and Coulomb excitation of exotic nuclei. The facility maintains an extensive physics-driven target and ion source development program, which has helped ISOLDE keep its international status for more than 35 years. Some recent experimental highlights and technical developments are discussed. [ABSTRACT FROM AUTHOR]

The FRS-RISING set-up at GSI uses secondary radioactive beams at relativistic energies for nuclear structure studies. At GSI the fragmentation or fission of stable primary beams up to 238U provide secondary beams with suffcient intensity to perform γ-ray spectroscopy. The RISING set-up is described and results of the first RISING campaign are presented. New experimental methods at relativistic energies are being investigated. Future experiments focus on state-of-the art nuclear structure physics covering exotic nuclei all over the nuclear chart. [ABSTRACT FROM AUTHOR]

Ion beam properties are often critical to experiments with rare isotopes. The ability to cool transverse motion and energy spread in a beam or modify its time structure can significantly improve many types of experiments. This ability is now a common feature in existing low-energy facilities and will play a central role in a number of next generation radioactive beam facilities. The basic physics underpinning the operation of these beam cooling devices is introduced below together with the key technical evolutions that have occurred since the previous ENAM conference. Examples of operating devices for various sources of radioactive ions are given, together with the performance presently achieved and improvements expected in the near future. [ABSTRACT FROM AUTHOR]

The ft values for superallowed 0+ → 0+ nuclear β transitions are nearly independent of nuclear-structure ambiguities and depend uniquely on the vector part of the weak interaction. They thus provide access to clean tests of some of the fundamental precepts of weak-interaction theory and can even probe physics beyond the standard model. We have just completed a new survey and overview of world data on such transitions, including not just the nine cases considered in the past, but also eleven more from T = 1 parents: even-even Tz = −1 nuclei from 18Ne to 42Ti; and odd-odd nuclei from 62Ga to 74Rb. These new cases all involve more exotic nuclei and, to yield comparable precision, present real experimental challenges. Nevertheless, three of these new cases are already known well enough to contribute — together with the nine well known transitions — to the setting of limits on fundamental weak-interaction parameters. The remaining eight cases show promise for making important contributions in future. [ABSTRACT FROM AUTHOR]

A nonzero atomic electric-dipole moment (EDM) at a level not far from current experimental limits would signify time-reversal violation from outside the Standard Model. EDMs are enhanced in atoms that have octupole-deformed nuclei. We report a careful self-consistent mean-field calculation of the time-reversal-violating nuclear Schiff moment —the quantity that induces an atomic EDM— in the octupole-deformed nucleus 225Ra. The self-consistent mean field in odd-A nuclei includes important effects of core polarization. The results of the calculation are encouraging for EDM experiments in the light actinides. Accurate calculations of Schiff moments in ordinary spherical and quadrupole-deformed nuclei such as 199Hg are also important. We describe work in progress on this more general problem. [ABSTRACT FROM AUTHOR]

In the framework of nuclear physics and at nuclear physics facilities a large number of different experiments can be performed which render the possibility to investigate fundamental symmetries and interactions in nature. In particular, the precise measurements of properties of fundamental fermions, searches for new interactions in β-decays, and violations of discrete symmetries have a robust discovery potential for physics beyond standard theory. Precise measurements of fundamental constants can be carried out as well. Low energy experiments allow probing of New Physics models at mass scales far beyond the reach of present accelerators or such planned for the future in the domain of high energy physics and at which predicted new particles could be produced directly. [ABSTRACT FROM AUTHOR]

We discuss pycnonuclear burning of highly exotic atomic nuclei in deep crusts of neutron stars, at densities up to 1013 g cm−3. As an application, we consider pycnonuclear burning of matter accreted on a neutron star in a soft X-ray transient (SXT, a compact binary containing a neutron star and a low- mass companion). The energy released in this burning, while the matter sinks into the stellar crust under the weight of newly accreted material, is sufficient to warm up the star and initiate neutrino emission in its core. The surface thermal radiation of the star in quiescent states becomes dependent on the poorly known equation of state (EOS) of supranuclear matter in the stellar core, which gives a method to explore this EOS. Four qualitatively different model EOSs are tested against observations of SXTs. They imply different levels of the enhancement of neutrino emission in massive neutron stars by 1) the direct Urca process in nucleon/hyperon matter; 2) pion condensates; 3) kaon condensates; 4) Cooper pairing of neutrons in nucleon matter with the forbidden direct Urca process. A low level of the thermal quiescent emission of two SXTs, SAX J1808.4-3658 and Cen X-4, contradicts model 4). Observations of SXTs test the same physics of dense matter as observations of thermal radiation from cooling isolated neutron stars, but the data on SXTs are currently more conclusive. [ABSTRACT FROM AUTHOR]

The Trojan-Horse method is an indirect approach to determine the low-energy astrophysical S-factor of direct nuclear reactions by studying closely related transfer reactions with three particles in the final state under quasi-free scattering conditions. The theoretical foundation and basic features of this approach are presented. General considerations for the application of method and two examples are discussed. [ABSTRACT FROM AUTHOR]

The identification of the astrophysical site and the specific conditions in which r-process nucleosynthesis takes place remain unsolved mysteries of astrophysics. The present paper illustrates the complexity of the r-process nucleosynthesis by describing the nuclear mechanisms taking place during the decompression of neutron star matter, a promising r-process site. Future challenges faced by nuclear physics in this problem are discussed, particularly in the determination of the radiative neutron capture rates by exotic nuclei close to the neutron drip line, as well as the need for improved global microscopic models for a reliable determination of all nuclear properties of relevance. [ABSTRACT FROM AUTHOR]

This manuscript reviews recent applications of the nuclear shell-model for the calculation of several quantities relevant for the core-collapse supernova dynamics and nucleosynthesis. These include electron capture rates and neutrino-nucleus cross sections for inelastic scattering. It is shown that electron capture rates on nuclei dominates over capture on free protons during the collapse leading to significant changes in the hydrodynamics of core collapse and bounce. Neutrino-nucleus cross sections at supernova neutrino energies can be determined from precise data on the magnetic dipole strength. The results agree well with large-scale shell-model calculations, validating this model. [ABSTRACT FROM AUTHOR]

We have constructed a new type of spin polarized solid proton target which can be operated under a low magnetic field of 0.08T and a high temperature of 100 K. We have measured for the first time the polarization asymmetry of an unstable beam of 6He at an energy of 71 MeV/u. Optical potential analyses have been carried out. [ABSTRACT FROM AUTHOR]

Despite a lot of experimental and theoretical progress the question of the r-process site and the origin of the heavy elements in nature remains one of the biggest open questions in nuclear astrophysics. We report first results from experiments with rare isotope beams of r-process nuclei at Michigan State University's National Superconducting Cyclotron Laboratory. This includes a first measurement of the half-life of the doubly-magic waiting point nucleus 78Ni, which serves as a major bottle-neck for the synthesis of heavy elements in many r-process models [ABSTRACT FROM AUTHOR]

A correct understanding of r-process nucleosynthesis requires the knowledge of nuclear-structure properties far from β-stability and a detailed description of the possible astrophysical environments. With respect to nuclear data, in recent years the main focus at CERN/ISOLDE has been put on the 132Sn region to explore the role of the N=82 shell closure and its consequences on the r-process matter flow through the A ≃ 130 Solar-System r-abundance peak. [ABSTRACT FROM AUTHOR]

The Canadian Penning trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of nuclides with short half-lives. Since the previous ENAM conference, many significant modifications to the apparatus were implemented to improve both the precision and efficiency of measurement, and now more than 60 radioactive isotopes have been measured with half-lives as short as one second and with a precision (Δm/m) approaching 10−8. The CPT mass measurement program has concentrated so far on nuclides of importance to astrophysics. In particular, measurements have been obtained of isotopes along the rp-process path, in which energy is released from a series of rapid proton-capture reactions. An X-ray burst is one possible site for the rp-process mechanism which involves the accretion of hydrogen and helium from one star onto the surface of its neutron star binary companion. Mass measurements are required as key inputs to network calculations used to describe the rp-process in terms of the abundances of the nuclides produced, the light-curve profile of the X-ray bursts, and the energy produced. This paper will present the precise mass measurements made along the rp-process path with particular emphasis on the "waiting-point" nuclides 68Se and 64Ge. [ABSTRACT FROM AUTHOR]

The time since ENAM' 01 is short by astrophysical standards, but this period has seen some exciting progress in the area of experimental nuclear astrophysics. New results have been obtained from facilities both large and small, with stable and exotic beams. In the process, we have learned a great deal about stellar structure and evolution. This talk highlights a few of many notable results obtained since ENAM '01 and will attempt to place them into an astrophysical context. In the process, it may be possible to see where the field is heading and what we might anticipate over the next three years. [ABSTRACT FROM AUTHOR]

Recent experimental data on relatively mass-asymmetric collisions show that fusion hindrance can be explained in terms of the onset of quasi-fission reactions. The influence of mass-asymmetry, shell effects and target deformation on such phenomena is presented and possible implications for super-heavy element production are discussed. [ABSTRACT FROM AUTHOR]

Over the past few years a great deal of new spectroscopic data has been obtained for transfermium nuclei. Recoil separators, coupled with modern target position and focal-plane spectrometers, allow detailed studies of the structure and decay properties of transfermium nuclei to be peformed. In-beam studies using the recoil-gating and recoil-decay tagging techniques mainly provide information on yrast states, whilst complementary focal-plane decay studies give access to non-yrast and isomeric structures. In-beam studies of nuclei in this region have largely been performed at ANL and JYFL, and decay experiments at GSI, JYFL, GANIL and ANL. The present contribution is focussed on recent developments and experiments carried out by a number of collaborating institutes at JYFL. [ABSTRACT FROM AUTHOR]

We have studied the dependence of the production cross-sections of the isotopes 282,283112 and 286-288114 on the excitation energy of the compound nuclei 286112 and 290114. The maximum cross-sections of the xn-evaporation channels for the reaction 238U(48Ca,xn)286-x 112 were measured to be: σ3n = 2.5-1.1+1.8 pb and σ4n = 0.6-0.5+1.6 pb; for the reaction 242Pu(48Ca,xn)290-x 114: σ2n ∼ 0.5 pb, σ3n = 3.6-1.7+3.4 pb and σ4n = 4.5-1.9+3.6 pb. In the reaction 233U(48Ca, 2-4n)277-279 112 we measured an upper cross-section limit of σxn ≤ 0.6 pb. An increase of σER in the reactions of actinide targets with 48Ca can be due to the expected increase of the survivability of the excited compound nucleus upon closer approach to the closed neutron shell N = 184. The observed nuclear decay properties of the nuclides with Z = 104-118 are compared with theoretical nuclear mass calculations and the systematic trends of α-decay properties. As a whole, they give a consistent pattern of decay of the 18 even-Z neutron-rich nuclides with Z = 104-118 and N = 163-177. [ABSTRACT FROM AUTHOR]

First investigations of chemical properties of bohrium (Z = 107) and hassium (Z = 108) showed an expected behaviour as ordinary members of groups 7 and 8 of the periodic table. Two attempts to study element 112 yielded some indication for a behaviour like a very volatile noble metal. However, a very recent experiment to confirm this preliminary observation failed. Two examples are described how chemical studies may help to support element discovery claims from purely physics experiments. The two examples are the discovery claims of the elements 112 and 115, respectively, where the progenies hassium and dubnium were chemically identified. [ABSTRACT FROM AUTHOR]

The search for superheavy elements has yielded exciting results for both the "cold fusion" approach with reactions employing Pb and Bi targets and the "hot fusion" reactions with 48Ca beams on actinide targets. In recent years the accelerator laboratories in Berkeley, Dubna and Darmstadt have been joined by new players in the game in France with GANIL, Caen, and in Japan with RIKEN, Tokyo. The latter yielding very encouraging results for the reactions on Pb/Bi targets which confirmed the data obtained at GSI. Beyond the successful synthesis, interesting features of the structure of the very heavy nuclei like the hint for a possible K-isomer in 270Ds or the population of states at a spin of up to 22ħ in 254No give a flavor of the exciting physics we can expect in the region at the very extreme upper right of the nuclear chart. To get a hand on it, a considerable increase in sensitivity is demanded from future experimental set-ups. High intensity stable beam accelerators, mass measurement in ion traps and mass spectrometers, as well as the possible employment of unstable neutron-rich projectile species, initially certainly only for systematic studies of reaction mechanism and nuclear structure features for lighter exotic neutron-rich isotopes, are some of the technological challenges which have been taken on. [ABSTRACT FROM AUTHOR]

Isoscalar pairing interaction and nuclear symmetry energy are investigated by means of the iso-cranking technique. Iso-cranking represents the lowest order approximation to isospin projection after variation. Due to its internal simplicity, it offers a very intuitive understanding of the structure of the nuclear symmetry energy as well as the response of the isoscalar and isovector pairing versus isospin. [ABSTRACT FROM AUTHOR]

The excitation phenomena in unstable nuclei are investigated in the framework of the relativistic quasiparticle random-phase approximation (RQRPA) in the relativistic Hartree-Bogoliubov model (RHB) which is extended to include effective interactions with explicit density-dependent meson-nucleon couplings. The properties of the pygmy dipole resonance (PDR) are examined in 132Sn and within isotopic chains, showing that already at moderate proton-neutron asymmetry the PDR peak energy is located above the neutron emission threshold. A method is suggested for determining the size of the neutron skin within an isotopic chain, based on the measurement of the excitation energies of the Gamow-Teller resonance relative to the isobaric analog state. In addition, for the first time the relativistic RHB + RQRPA model, with tensor ω meson-nucleon couplings, is employed in calculations of β-decay half-lives of nuclei of the relevance for the r-process. [ABSTRACT FROM AUTHOR]

Structure of carbon and neon isotopes is investigated by deformed Skyrme Hartree-Fock and shell model calculations. We point out that the quadrupole deformations of C and Ne isotopes have strong isotope dependence as a typical example of the evolution of deformations in nuclei. It is shown also that the quadrupole moments and the magnetic moments of the odd C isotopes depend clearly on assigned configurations, and their experimental data will be useful to determine the spin-parities and the deformations of the ground states of these nuclei. The electric quadrupole (E2) transitions in even C and Ne isotopes are also studied. The isotope dependence of the E2 transition strength is reproduced properly, although the calculated strength overestimates an extremely small observed value in 16C. [ABSTRACT FROM AUTHOR]

Starting from successful self-consistent mean-field models, this paper discusses why and how to go beyond the mean-field approximation. To include long-range correlations from fluctuations in collective degrees of freedom, one has to consider symmetry restoration and configuration mixing, which give access to ground-state correlations and spectroscopy. [ABSTRACT FROM AUTHOR]

The shell-model effective interaction GXPF1 is tested for the description of unstable pf-shell nuclei. The GXPF1 successfully describes the N = 32 shell gap in Ca, Ti and Cr isotopes, while the deviation of predicted Ex(21+) in 56Ti from the recent experimental data requires the modification of the Hamiltonian especially in the T = 1 matrix elements related to the p1/2 and f5/2 orbits. The modified interaction gives improved description simultaneously for all these isotope chains. [ABSTRACT FROM AUTHOR]

A consistent description of weakly bound and unbound nuclei requires an accurate description of the particle continuum properties when carrying out multiconfiguration mixing. This is the domain of the Gamow Shell Model (GSM) which is the multiconfigurational shell model in the complex k-plane formulated using a complete Berggren ensemble representing bound single-particle (s.p.) states, s.p. resonances, and non-resonant complex energy continuum states. We shall discuss the salient features of effective interactions in weakly bound systems and show selected applications of the GSM formalism to p-shell nuclei. Finally, a development of the new non-perturbative scheme based on Density Matrix Renormalization Group methods to select the most significant continuum configurations in GSM calculations will be discussed shortly. [ABSTRACT FROM AUTHOR]

We report preliminary large scale ab initio calculations of ground and excited states of 16O using quantum chemistry inspired coupled cluster methods and realistic two-body interactions. By using the renormalized Hamiltonians obtained with a no-core G-matrix approach, we obtain the virtually converged results at the level of two-body interactions. Due to the polynomial scaling with the system size that characterizes coupled cluster methods, we can probe large model spaces with up to seven major oscillator shells, for which standard non-truncated shell-model calculations are not possible. [ABSTRACT FROM AUTHOR]