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Öğe Discovery of the proton emitting nucleus Re-159(AMER INST PHYSICS, 2007) Joss, D. T.; Darby, I. G.; Page, R. D.; Uttsitalo, J.; Eeckhaudt, S.; Grahn, T.; Nyman, A.; Ferreira, LS; Arumugam, PThe observation of the new nuclide Re-159 provides important insights into the evolution of single-particle structure in heavy nuclei beyond the proton drip line. The nuclide Re-159 was synthesised in the reaction Cd-106(Ni-58, p4n) and identified via its proton radioactivity using the RITU gas-filled separator and the GREAT focal-plane spectrometer. Comparisons of the measured proton energy (E-p = 1805 +/- 20 keV) and decay half-life (t(1/2) = 21 +/- 4 ps) with values calculated using the YIKB method indicate that the proton is emitted from an h(11/2) state. The implications of these results for future experimental investigations into even more proton unbound Re isotopes using in-flight separation techniques are considered.Öğe In-beam gamma-ray spectroscopy of the N=85 isotones W-159 and Re-160(AMER PHYSICAL SOC, 2011) Sapple, P. J.; Page, R. D.; Joss, D. T.; Bianco, L.; Grahn, T.; Pakarinen, J.; Julin, R.Excited states have been identified in the isotones W-159(74) and Re-160(75), which were produced in fusion-evaporation reactions of a beam of 310-MeV Ni-58 ions with an isotopically enriched Cd-106 target. The strongest gamma-ray transitions in W-159 and Re-160 are interpreted as continuing the regular sequence of states identified in lighter N = 85 isotones that are built upon 9/2(-) and 10(+) states, respectively. The half-life of Hf-155, the beta-decaying daughter of the a decay of W-159, was measured with improved precision to be 840 +/- 30 ms.Öğe 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.Öğe Probing single-particle structures beyond the proton drip line(AMER INST PHYSICS, 2007) Page, R. D.; Bianco, L.; Darby, I. G.; Joss, D. T.; Grahn, T.; Herzberg, R. -D.; Juutinen, S.; Ferreira, LS; Arumugam, PSingle-particle energies have been investigated in the closed neutron shell proton emitter Ta-155. The Ta-155 nuclei were populated through the alpha decay of Re-159, which has been observed for the first time. The (159)Rc nuclei were produced in reactions of 300 MeV Ni-58 ions with an isotopically enriched Cd-106 target, separated in-flight using the RITU separator and implanted into the GREAT spectrometer. The Re-159 a decay emanates from the proton-emitting pi h(11/2) state and populates a state in Ta-155 which decays by the emission of a proton from a pi h(11/2) orbital. The results fit in with the systematics of proton and alpha-particle separation energies in the region, but disagree with the previously reported decay properties of Ta-155.Öğe Probing the limit of nuclear existence: Proton emission from Re-159(ELSEVIER SCIENCE BV, 2006) Joss, D. T.; Darby, I. G.; Page, R. D.; Uusitalo, J.; Eeckhaudt, S.; Grahn, T.; Nyman, M.The observation of the new nuclide Re-159(75)84 provides important insights into the evolution of single-particle structure and the mass surface in heavy nuclei beyond the proton drip line. This nuclide, 26 neutrons away from the nearest stable rhenium isotope, was synthesised in the reaction Cd-106(Ni-58, p4n) and identified via its proton radioactivity using the RITU gas-filled separator and the GREAT focal-plane spectrometer. Comparisons of the measured proton energy (E-p = 1805 +/- 20 keV) and decay half-life (t(1/2) = 21 +/- 4 mu s) with values calculated using the WKB method indicate that the proton is emitted from an h(11/2) state. The implications of these results for future experimental investigations into even more proton unbound nuclei using in-flight separation techniques are considered. (c) 2006 Elsevier B.V. All rights reserved.Öğe Reduced transition probabilities along the yrast line in 166W(Amer Physical Soc, 2017) Saygi, B.; Joss, D. T.; Page, R. D.; Grahn, T.; Simpson, J.; O'Donnell, D.; Alharshan, G.Lifetimes of excited states in the yrast band of the neutron-deficient nuclide W-166 have been measured utilizing the DPUNS plunger device at the target position of the JUROGAM II gamma-ray spectrometer in conjunction with the RITU gas-filled separator and the GREAT focal-plane spectrometer. Excited states in W-166 were populated in the Mo-92(Kr-78, 4p) reaction at a bombarding energy of 380 MeV. The measurements reveal a low value for the ratio of reduced transitions probabilities for the lowest-lying transitions B(E2; 4(+)-> 2(+)) / B(E2; 2(+)-> 0(+)) = 0.33(5), compared with the expected ratio for an axially deformed rotor (B-4/2 = 1.43).
