Search results for "SHELL"
showing 10 items of 748 documents
Evolution of nuclear structure in neutron-rich odd-Zn isotopes and isomers
2017
Collinear laser spectroscopy was performed on Zn (Z=30) isotopes at ISOLDE, CERN. The study of hyperfine spectra of nuclei across the Zn isotopic chain, N=33–49, allowed the measurement of nuclear spins for the ground and isomeric states in odd-A neutron-rich nuclei up to N=50. Exactly one long-lived (&
Mirror energy differences above the 0f7/2 shell: First γ-ray spectroscopy of the Tz = −2 nucleus 56Zn
2021
5 pags., 4 figs.
Spins, Electromagnetic Moments, and Isomers of $^{107-129}Cd$
2013
The neutron-rich isotopes of cadmium up to the N=82 shell closure have been investigated by high-resolution laser spectroscopy. Deep-UV excitation at 214.5 nm and radioactive-beam bunching provided the required experimental sensitivity. Long-lived isomers are observed in 127Cd and 129Cd for the first time. One essential feature of the spherical shell model is unambiguously confirmed by a linear increase of the 11/2- quadrupole moments. Remarkably, this mechanism is found to act well beyond the h11/2 shell. The neutron-rich isotopes of cadmium up to the N=82 shell closure have been investigated by high-resolution laser spectroscopy. Deep-uv excitation at 214.5 nm and radioactive-beam bunchin…
Dispersive approach to the nuclear compton amplitude and exchange effects
1981
We discuss the limitation of the standard approach to exchange current effects from photonuclear sum rules. We propose to look for an energy-independent contribution to the real part of the forward Compton-scattering amplitude below pion threshold. Experimental data on photonuclear cross-sections are used to calculate the real part of the amplitude, by means of an once-subtracted dispersion relation. The analysis is made for2H,7Li and9Be at energies varying between 50 and 150 MeV. A remarkably stable value ofK=0.60 is extracted for deuterium. For 1p shell nuclei, the main uncertainty is due to the lack of data above 300 MeV.
Gamow-Teller Beta Decay of Neutron Rich Tc, Ru, Rh and Pd Isotopes
1988
During recent experiments at the IGISOL-facility several new neutron rich nuclides have been discovered, including the first direct observations of the beta decays of 111Tc, 112Ru, 113Ru, 114Ru, 113Rh, 115Rh, 116Rh and 118Pd. The role of the νg7/2 → πg9/2 transformation in the beta decays of the odd-odd 110–116Rh and the even-even 114–118Pd isotopes is shown to be dominant. The experimental results are compared with shell model calculations including deformation and pairing.
Properties of heavy nuclei measured at the GSI SHIP
2004
Abstract The nuclear shell model predicts that the next doubly magic shell-closure beyond 208 Pb is at a proton number Z = 114, 120, or 126 and at a neutron number N = 172 or 184. The outstanding aim of experimental investigations is the exploration of this region of spherical ‘Super-Heavy Elements’ (SHEs). The measured decay data reveal that for the heaviest elements, the dominant decay mode is α emission, not fission. Decay properties as well as reaction cross-sections are compared with results of theoretical investigations. Finally, plans are presented for the further development of the experimental set-up and the application of new techniques.At a higher sensitivity, the exploration of …
Shell-model study of partial muon-capture rates in light nuclei
1998
Abstract The nuclear shell model is used to study ordinary muon capture of light nuclei in the p, sd and p-sd shell-model spaces. Several well-established two-body interactions are applied to calculate the involved nuclear matrix elements and the emerging results are compared with each other. The resulting theoretical partial muon-capture rates are compared with experimental data and their stability against different model spaces and interactions studied. The effects of the induced-pseudoscalar strength, C p , on the capture rates is discussed. The relation between the allowed partial muon capture rates and the Gamow-Teller strength function is stressed.
Storage-ring experiments with exotic nuclei: from mass measurements to the future
2004
Direct mass measurements with electron-cooled ions coasting in a heavy-ion storage ring allow the mapping of large areas of the nuclear chart, well suited to explore new regions and to investigate isospin effects as well as structure changes far-off stability. In this contribution first results will be discussed, experimental masses will be compared to theoretical predictions. A study of the isospin dependence of shell strength and pairing will be made.
Analysis of the 2νββ decay and muon capture reactions for the mass A = 46 and A = 48 nuclei using the nuclear shell model
2005
We discuss the two-neutrino double-beta decays of 46Ca and 48Ca by using the nuclear shell model with well-tested two-body interactions. We also discuss the ordinary muon-capture (OMC) reaction on the final nuclei, 46Ti and 48Ti, of these decays. The OMC leads to the virtual states of the intermediate nuclei, 46Sc and 48Sc, in these double-beta decays.
Probing shapes of very neutron deficientZ≈82 nuclei using the recoil-decay tagging method
1997
The JYFL gas-filled recoil separator, RITU, combined with efficient Ge-detector arrays has been employed in in-beam γ-ray studies of very neutron-deficient nuclei close to theZ=82 shell. Gamma-rays from nuclei produced at the few μb cross-section level have been detected.