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The y decay in the radiative fusion reaction 9~ 9~ 18~ has been observed in an array of NaI detectors. States up to 6 § in the yrast sequence of ~ 8~ are tentatively assigned and suggest the coexistence of weakly oblate and strongly prolate nuclear shapes. The difference in potential energy between the two inferred shapes has dropped to about 200 keV, continuing the downward trend observed in the heavier even isotopes ~s8-1SZHg"

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The activation cross sections of (d, p), (d, 2n), (d, 3n), and (d, 2p) reactions on 63,65 Cu were measured in the energy range from 4 to 20 MeV using the stacked-foils technique. Then, following the available elastic-scattering data analysis that provided the optical potential for reaction cross sections calculations, an increased effort has been devoted to the breakup mechanism, the direct reaction stripping, and the pre-equilibrium and compound-nucleus cross section calculations, corrected for the breakup and stripping decrease of the total reaction cross section. The overall agreement between the measured and calculated deuteron activation cross sections proves the correctness of the nuclear mechanisms account, next to the simultaneous analysis of the elastic-scattering and reaction data.

The presence of isospin mixing in the T = 5/2 ground state of 71 As was studied via anisotropic positron emission from oriented nuclei. A small isospin-forbidden Fermi component in the predominantly Gamow-Teller β decay was established, corresponding to an isospin mixing probability of (13 ± 4) × 10 −6 . The sign of the magnetic moment of 71 As was determined to be positive.

The nuclear magnetic moment of the nucleus 59 Cu, with one proton and two neutrons outside the closed N = Z = 28 shells, was measured in an on-line experiment combining ␤-NMR with low temperature nuclear orientation and with particle detectors operating at a temperature of about 10 K. From the data the center frequency ͑B ext =0͒ = 209.51͑22͒ MHz was derived. Using the hyperfine field of Cu in host iron from the literature the result for the moment is ͓ 59 Cu͔ = + 1.891͑9͒ N , which reveals a large deviation from the proton p 3/2 single-particle value. This provides strong experimental evidence for a massive shell breaking at 56 Ni.

Abstract. For validating activation cross-section data in the energy range relevant to IFMIF (International Fusion Material Irradiation Facility), the fast neutron sources were developed utilizing the NPI variable-energy cyclotron U-120M. Novel concept of source reaction was investigated for a generation of the white -(IFMIF-like) -spectrum on NPI cyclotron. The deuteron break-up process induced by 37 MeV protons on flowing heavy water target was found to produce neutrons with high intensity, mean energy of 14 MeV and spectrum extending to 32 MeV. The small-size samples (diameter of 15 mm) are irradiated at neutron flux up to 10 11 n/cm 2 /s in this source. The quasi-monoenergetic neutron field in the energy range from 20 to 35 MeV is produced using standard 7 Li(p,n) reaction on thin (carbon backed) lithium foil. The p-Li source produces neutron flux up to 10 9 n/cm 2 /s. The present work deals with methodical, technical and functional characteristics of p-D 2 O and p-7 Li neutron sources. The determination of spectral flux at position of irradiated samples is described in details. A summary of present and next program of experiments is outlined.