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The first results from the Stopped Beam RISING experimental campaign performed at the GSI laboratory in Darmstadt, Germany, are presented. RISING (Rare ISotope INvestigations at GSI) constitutes a major new experimental program in European nuclear structure physics research aimed at using relativistic-energy, projectile-fragmentation reactions to study nuclei with exotic proton-to-neutron ratios. This paper introduces the physics aims of the Stopped RISING collaboration and presents some technical details and initial results from experiments using the RISING array to study decays from metastable nuclear states in both proton and neutron-rich nuclei. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

High Power Proton Accelerators (HPPAs) are studied for several projects based on high-flux neutron sources driven by proton or deuteron beams. Since the front end is considered as the most critical part of such accelerators, the two French national research agencies CEA and CNRS decided to collaborate in 1997 to study and build a High-Intensity Proton Injector (IPHI). The main objective of this project is to master the complex technologies used and the concepts of manufacturing and controlling the HPPAs. Recently, a collaboration agreement was signed with CERN and led to some evolutions in the design and in the schedule. The IPHI design current was maintained at 100 mA in Continuous Wave mode. This choice should allow to produce a high reliability beam at reduced intensity (typically 30 mA) tending to fulfill the Accelerator Driven System requirements. The output energy of the Radio Frequency Quadrupole (RFQ), was reduced from 5 to 3 MeV, allowing then the adjunction and the test, in pulsed operation of a chopper line developed by CERN for the Superconducting Proton Linac (SPL). In a final step, the IPHI RFQ and the chopper line should become parts of the SPL injector. In this paper, the IPHI project and the recent evolutions are reported together with the construction and operation schedule. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Proton and neutron data as well as photon data are necessary in various intermediate energy applications. To meet these requirements, many groups in the world continue some activities concerning nuclear data evaluation in the energy range above 20 MeV, which is the upper limit of conventional general-purpose evaluated nuclear data files. In this paper, reviewed is brief history of intermediate energy nuclear data development as well as Pearlstein’s contribution for it. Present status of world evaluated nuclear data files in the intermediate energy region is reported as well as evaluation methodology and sample results of evaluation and integral benchmark tests by using the case of JENDL High Energy File as an example. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

A new evaluated nuclear data library has been created. The library consists of two sub-libraries for neutron and proton incident particles. The first version of neutron sub-library has been completed and described in the present paper. The library contains nuclear data for transport, heating, and shielding applications for 242 nuclides ranging in atomic number from 8 to 82 in the energy region of primary neutrons from 10-5 eV to 150 MeV. Data below 20 MeV are taken mainly from ENDF/B-VI (Revision 8) and for some nuclides, from the JENDL-3.3 and JEFF-3.0 libraries. The evaluation of emitted particle energy and angular distributions at the energies above 20 MeV was performed with the help of the ALICE/ASH code and the analysis of available experimental data. The total cross sections, elastic cross sections, and elastic scattering angular distributions were calculated with the help of the coupled channel model. The results of the calculation were adjusted to the data from ENDF/B-VI, JENDL-3.3m or JEFF-3.0 at the neutron energy equal to 20 MeV. The library is written in ENDF/B-VI format using the MF=3/MT=5 and MF=6/MT=5 representations. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The author discusses some of the challenges that future nuclear modeling may face in order to improve the description of the nuclear structure. One challenge is related to the need for A-body nuclear interactions justified by various contemporary nuclear physics studies. Another challenge is related to the discrepancy in the NNN contact interaction parameters for 3He and 3H that suggests the need for accurate proton and neutron masses in the future precision calculations. [ABSTRACT FROM AUTHOR]

The paper reports on experimental developments for studies of decays of proton radioactive nuclei on the Argonne Fragment Mass Analyzer. The results illustrate that there is a clear proton decay rate sensitivity to the unpaired neutron orbital in highly deformed odd-odd nuclei consistent with the Influential Spectator Model of Ferreira and Maglione. No such sensitivity is observed for the proton decay rates of spherical odd-odd nuclei studied here. The first ever study of proton decay from a nucleus, 135Tb, produced via 1p6n fusion evaporation is also reported. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

The spectroscopy of fission fragments, obtained by the 18O+208Pb fusion-fission reaction at 85 MeV bombarding energy, has been performed with the Euroball IV γ-array. High-spin states in many neutron-rich Se, Br, Kr and Rb of the 78Ni region nuclei have been identified for the first time. Several physical aspects which govern the nuclear structure in this mass region are underlined thanks to the new results. Among those, empirical values of the residual proton-neutron interactions have been extracted for the πf5/2xvd5/2 and πp3/2xvd5/2 configurations. [ABSTRACT FROM AUTHOR]

The systematics of the πh11/2xνh11/2 and πh11/2xνs1/2 isomeric configurations were studied for the odd-Z N = 77 isotones near the proton dripline. The spin and parity of Iπ = 8+ and 5- were deduced for the isomers in 140Eu and 142Tb. No evidence for the expected 1+ ground-state was found in the 144Ho decay data. The proton emission from 146Tm was restudied and the spin and parity values of Iπ = 10+ and 5- were established for 146mTm and 146gsTm, respectively. The interpretation of the observed decay properties and structure of the proton-emitting states was made by accounting for deformation and proton and neutron coupling to the core excitations. [ABSTRACT FROM AUTHOR]

Nuclei with equal number of protons and neutrons have many interesting properties connected with high probability of alpha-particle correlations. However, no such nuclei heavier than 100Sn were identified until now. Meanwhile, they can demonstrate some new unusual features, e.g. the existing of alpha-particle skin, the appearance of a new domain of cluster radioactivity and the most aspiring one, alpha-particle Bose condensate. Current situation in the field and possible experimental approaches are discussed. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A scattering study of ∼ 30 keV neutrons from H2O, D2O and H2O/D2O mixtures was carried out to search for a ∼ 40% anomalous drop in the n-p scattering cross section. Such an anomaly was reported using 10–200eV neutrons scattered from many H-containing compounds. The anomaly was attributed to n-scattering from quantum entangled proton pairs in the sample. In the present measurement no anomaly was observed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

In the present work both the (α,γ) and (p,γ) cross sections on the p-nucleus 106Cd have been measured in the energy range relevant to the astrophysical p-process. The results are compared with the predictions of the statistical model calculations implemented with the NON-SMOKER code using different input parameters. The proton capture cross section has also been measured for 108Cd. The α + 106Cd optical potential, an important input parameter for the 106Cd(α,γ) reaction rate determination, can be determined directly by measuring the deviation from the Rutherford scattering in the 106Cd(α,α)106Cd elastic scattering experiment. This experiment has also been performed in a wide angular range and the results are compared with different global optical potentials. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The discovery of the currently known most neutron- and proton-rich nuclei is compiled. The compilation includes the year and method of discovery of the last known bound and the first unbound nuclei along the neutron and proton driplines. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Neutron- and proton-induced fission cross-sections of the lead isotopes 204,206–208Pb and 205Tl in the intermediate energy region have been measured at the Svedberg Laboratory in Uppsala, Sweden. Average fissilities of the composite nuclei and the dependence on the nucleon energy and the parameter Z2/A were determined. On this basis, the correlation between the proton- and neutron-induced fission cross sections has been established in the atomic mass region A ∼ 200 and for nucleon energies above 50 MeV, where shell effects do not play a very significant role. The correlation is discussed in the frame of results from calculations by the code TALYS. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The issue of correlations between protons and neutrons has become a major focus of nuclear structure research along the proton dripline. The strength of these correlations determined when nuclear binding ends. The correlations can have isospin T=1, just like &lrquo;normal” neutron-neutron and proton-proton pairs, or have more exotic structure in a deuteron-like T=0 configuration. I will discuss ways of studying these correlations and their relative importance. Odd-odd N=Z nuclei are good laboratories for this work. [ABSTRACT FROM AUTHOR]