Yazar "Judson, D. S." seçeneğine göre listele

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    Decay of the high-spin isomer in Re-160: Changing single-particle structure beyond the proton drip line
    (ELSEVIER SCIENCE BV, 2011) Darby, I. G.; Page, R. D.; Joss, D. T.; Simpson, J.; Bianco, L.; Cooper, R. J.; Judson, D. S.
    A new high-spin isomeric state (t(1/2) = 2.8 +/- 0.1 mu s) in Re-160 has been identified. This high-spin isomer is unique in that it only decays by gamma-decay and not by proton or alpha-particle emission as is the case in every other proton emitter between Z = 64 and 80. Shell model calculations indicate how the convergence of the h(9/2) and f(7/2) neutron levels in this region could open up a gamma-decay path from the high-spin isomer to the low-spin ground state of 160Re. providing a natural explanation for this anomalous absence of charged-particle emission. The consequences of these observations for future searches for proton emission from even more exotic nuclei and in-beam spectroscopic studies are considered. (C) 2010 Elsevier B.V. All rights reserved.
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    Precision measurements of proton emission from the ground states of Ta-156 and Re-160
    (AMER PHYSICAL SOC, 2011) Darby, I. G.; Page, R. D.; Joss, D. T.; Bianco, L.; Grahn, T.; Judson, D. S.; Leino, M.
    The decays of the pi d(3/2) ground states of Ta-156 and Re-160 have been studied in detail using the GREAT spectrometer. More than 7000 Re-160 nuclei were produced in reactions of 290- and 300-MeV Ni-58 ions with an isotopically enriched Cd-106 target and separated in flight using the RITU separator. The proton and alpha decays of the pi d(3/2) level were confirmed and the half-life and branching ratios of this state were determined with improved precision to be t(1/2) = 611 +/- 7 mu s and b(p) = 89 +/- 1% and b(alpha) = 11 +/- 1%, respectively. The alpha-decay branch populated the ground state of Ta-156, allowing improved values for the proton-decay energy and half-life to be obtained (E-p = 1011 +/- 5 keV; t(1/2) = 106 +/- 4 ms). The beta decay of this level was identified for the first time and a branching ratio of b(beta) = 29 +/- 3% was deduced. The spectroscopic factors deduced from these measurements are compared with predictions.