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27 results on '"gas-filled recoil separator"'

1. α-decay properties of new neutron-deficient isotope 203Ac

Author

J.G. Wang, Z.G. Gan, Z.Y. Zhang, M.H. Huang, L. Ma, M.M. Zhang, H.B. Yang, C.L. Yang, Y.H. Qiang, X.Y. Huang, Z. Zhao, S.Y. Xu, Z.C. Li, L.X. Chen, L.C. Sun, H. Zhou, X. Zhang, X.L. Wu, Y.L. Tian, Y.S. Wang, J.Y. Wang, W.X. Huang, M.L. Liu, Z.W. Lu, Y. He, Z.Z. Ren, S.G. Zhou, X.H. Zhou, H.S. Xu, V.K. Utyonkov, A.A. Voinov, Yu.S. Tsyganov, and A.N. Polyakov

Subjects
New isotope, Neutron-deficient nuclei, α decay, Gas-filled recoil separator, Physics, QC1-999
Abstract

A new isotope 203Ac was produced in the reaction 40Ca + 169Tm at beam energy of 226 MeV. One correlated α-decay chain was attributed to 203Ac. The α-particle energy and half-life were determined to be 8217(16) keV and 56−26+269 μs, respectively. The reduced α-decay width (δ2) of 203Ac was deduced to be 1096−906+921 keV, which indicates a favored α decay. The systematics of δ2 and single-particle energy levels indicate that the new state probably arises from the intruder s1/2 configuration, which shows an onset of deformation in Ac isotopes. The proton separation energy Sp of 203Ac was extracted as −1214(22) keV and the systematics of Sp for odd-A isotopes beyond proton drip line were discussed.

Published
2024
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2. α decay of the new isotope 204Ac

Author

M.H. Huang, Z.G. Gan, Z.Y. Zhang, L. Ma, J.G. Wang, M.M. Zhang, H.B. Yang, C.L. Yang, X.Y. Huang, Z. Zhao, S.Y. Xu, L.X. Chen, X.J. Wen, Y.F. Niu, C.X. Yuan, Y.L. Tian, Y.S. Wang, J.Y. Wang, M.L. Liu, Y.H. Qiang, W.Q. Yang, H.B. Zhang, Z.W. Lu, S. Guo, W.X. Huang, Y. He, Z.Z. Ren, S.G. Zhou, X.H. Zhou, H.S. Xu, V.K. Utyonkov, A.A. Voinov, Yu.S. Tsyganov, and A.N. Polyakov

Subjects
New isotope, Neutron-deficient, α-particle energy, Half-life, Gas-filled recoil separator, Excitation function, Physics, QC1-999
Abstract

A new proton-unbound isotope 204Ac was produced in the fusion-evaporation reaction Tm(40169Ca,5n)204Ac and identified via the recoil-α correlation at the gas-filled recoiled separators SHANS2 and SHANS. The excitation function for producing 204Ac was measured and the optimal beam energy was evaluated to be 212 MeV. Nineteen ER - α1 - α2 - α3 decay chains were observed for this isotope. Based on these chains, the α-particle energy and half-life of 204Ac were determined to be 7948(15) keV and 7.4−1.4+2.2 ms, respectively. Both are consistent with the theoretical prediction. The reduced α-decay width was deduced to be 49−15+10 keV, which indicates a favored α decay for 204Ac. In addition, more precise decay properties of Eα = 7883(15) keV and T1/2 = 7.7−1.6+2.7 ms were obtained for 205Ac.

Published
2022
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3. A multi-reflection time-of-flight mass analyzer at IMP/CAS.

Author

Wang, Jun-Ying, Tian, Yu-Lin, Wang, Yong-Sheng, Gan, Zai-Guo, Zhou, Xiao-Hong, Xu, Hu-Shan, and Huang, Wen-Xue

Subjects
*MASS spectrometers, *HEAVY ion fusion reactions, *NUCLEAR structure, *TIME-of-flight mass spectrometry, *MASS measurement, *NEW product development, *SPECTROMETERS
Abstract

Accurate mass data of transuranium nuclei is particularly important for the study of superheavy nuclei and the investigation of "island of stability". A low energy mass spectrometer to provide high-precision mass measurement and isobaric separation of short-lived fusion-evaporation reaction products is planned at the Spectrometer for Heavy Atom and Nuclear Structure (SHANS). A multi-reflection time-of-flight mass analyzer for SHANS has been designed and constructed and is being tested now. In the in-trap-lift mode, the latest simulation results by using SIMION give a maximal mass resolving power of 1.6 × 105 for a TOF of 6.4 ms, and the preliminary test results by applying the simulated voltages show that its mass resolving power has reached ≈ 7000 for a TOF of 1.6 ms. [ABSTRACT FROM AUTHOR]

Published
2020
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4. Double-layered target and identification method of individual target correlated with evaporation residues.

Author

Kaji, D. and Morimoto, K.

Subjects
*DOUBLE layers (Astrophysics), *ROTATIONAL motion, *EVAPORATION (Chemistry), *SUPERHEAVY elements, *NUCLEAR energy
Abstract

A double-layered target system and an identification method (target ID) for individual targets mounted on a rotating wheel using correlation with evaporation residues were newly developed for the study of superheavy elements (SHE). The target system can be used in three modes: conventional single-layered mode, double-layered mode, and energy-degrader mode. The target ID method can be utilized for masking a target, measuring an excitation function without changing the beam energy from the accelerator, and searching for SHE nuclides using multiple targets during a single irradiation. [ABSTRACT FROM AUTHOR]

Published
2015
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5. Testing nuclear structure near shell closures at WNSL.

Author

Werner, V., Berant, Z., Bunce, M., Casperson, R. J., Casten, R. F., Heinz, A., Henning, G., Lüttke, R., McCutchan, E. A., Parker, P., Qian, J., Schmidt, A., Shoraka, B., Terry, J. R., Williams, E., and Winkler, R.

Subjects
*NUCLEAR research, *NUCLEAR structure, *NEUTRONS, *PROTONS, *GAMMA rays, *SPECTRUM analysis, *NUCLEAR physics
Abstract

A brief overview of the experimental capabilities at the Wright Nuclear Structure Laboratory (WNSL) is given. Results of selected recent experiments, which test nuclear structure in the vicinity of shell closures, will be shown. These experiments include the investigation of proton-neutron symmetric and mixed-symmetric structures, and their emergence from the underlying shell structure in different mass regions, using a variety of techniques. [ABSTRACT FROM AUTHOR]

Published
2009
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6. Decays of New Nuclides and Isomers Beyond the Proton Drip Line—The Influence of Neutron Configurations.

Author

Page, R. D., Bianco, L., Darby, I. G., Joss, D. T., Simpson, J., Al-Khalili, J. S., Cannon, A. J., Cooper, R. J., Eeckhaudt, S., Ertürk, S., Gall, B., Grahn, T., Greenlees, P. T., Hadinia, B., Jones, P. M., Judson, D. S., Julin, R., Juutinen, S., Ketelhut, S., and Labiche, M.

Subjects
*EXOTIC nuclei, *NEUTRONS, *PROTONS, *IONS, *SPECTROMETERS
Abstract

The energy of the vh9/2 orbital in nuclei above N = 82 drops rapidly in energy relative to the vf7/2 orbital as the occupancy of the πh11/2 orbital increases. These two neutron orbitals become nearly degenerate as the proton drip line is approached. In this work, we have discovered the new nuclides 161Os and 157W, and studied the decays of the proton emitter 160Re in detail. The 161Os and 160Re nuclei were produced in reactions of 290, 300 and 310 MeV 58Ni ions with an isotopically enriched 106Cd target, separated in-flight using the RITU separator and implanted into the GREAT spectrometer. The 161Os α a decays populated the new nuclide 157W, which decayed by β-particle emission. The β decay fed the known α-decaying 1/2+ and 11/2- states in 157Ta, which is consistent with a vf7/2 ground state in 157W. The measured α-decay energy and half-life for 161Os correspond to a reduced α-decay width that is compatible with s-wave α-particle emission, implying that its ground state is also a vf7/2 state. Over 7000 160Re nuclei were produced and the γ decays of a new isomeric state feeding the πd3/2 level in 160Re were discovered, but no evidence for the proton or a decay of the expected πh11/2 state could be found. The isomer decays offer a natural explanation for this non-observation and provides a striking example of the influence of the near degeneracy of the vh9/2 and vf7/2 orbitals on the properties of nuclei in this region. [ABSTRACT FROM AUTHOR]

Published
2008
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7. Spectroscopy of the neutron-deficient isobars 163Re and 163W using tagging techniques.

Author

Joss, D. T., Thomson, J., Scholey, C., Ertürk, S., Simpson, J., Page, R. D., Bianco, L., Cederwall, B., Darby, I. G., Eeckhaudt, S., Gomez-Hornillos, M. B., Grahn, T., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Lagergren, K., Leino, M., and Leppännen, A.-P.

Subjects
*NUCLEAR isobars, *EXOTIC nuclei, *SPECTROMETERS, *IONS, *SPECTRUM analysis
Abstract

Selective tagging techniques have been used to establish new band structures in the transitional isobars 163Re and 163W. These nuclei were produced in the 106Cd(60Ni, xp yn γ) reaction at a bombarding energy of 270 MeV. Prompt γ rays were detected at the target position using the JUROGAM spectrometer while recoiling ions were separated by the RITU separator and implanted into the GREAT spectrometer. At low spin, the yrast band of 163Re is shown to be a strongly coupled collective band based on a proton h11/2 configuration. In 163W, the decay path of the 13/2+ isomeric state to the ground state has been identified and negative parity structures based on the ground state established. [ABSTRACT FROM AUTHOR]

Published
2008
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8. Discovery of the proton emitting nucleus 159Re.

Author

Joss, D. T., Darby, I. G., Page, R. D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A.-P., Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A. N., and Al-Khalili, J. S.

Subjects
*NUCLEAR physics, *NUCLEAR reactions, *RADIOACTIVITY, *PROTONS, *SPECTRUM analysis instruments, *SPECTROMETERS
Abstract

The observation of the new nuclide 159Re provides important insights into the evolution of single-particle structure in heavy nuclei beyond the proton drip line. The nuclide 159Re was synthesised in the reaction 106Cd(58Ni,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 (Ep = 1805±20 keV) and decay half-life (t1/2 = 21±4 μs) with values calculated using the WKB method indicate that the proton is emitted from an h11/2 state. The implications of these results for future experimental investigations into even more proton unbound Re isotopes using in-flight separation techniques are considered. [ABSTRACT FROM AUTHOR]

Published
2007
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9. Experiments on Synthesis of the Heaviest Element at RIKEN.

Author

Morita, K., Morimoto, K., Kaji, D., Akiyama, T., Goto, S., Haba, H., Ideguchi, E., Kanumgo, R., Katori, K., Kikunaga, H., Koura, H., Kudo, H., Ohnishi, T., Ozawa, A., Sato, N., Suda, T., Sueki, K., Tokanai, F., Xu, H., and Yamaguchi, T.

Subjects
*HEAVY elements, *ALPHA rays, *RADIOACTIVE decay, *NUCLEAR fission, *NUCLEAR physics
Abstract

At the Institute of Physical and Chemical Research (RIKEN) a series of experiments studying the productions and their decays of the heaviest elements have been performed by using a gas-filled recoil ion separator GARIS. Results on the isotope of the 112th element, 277112, and on that of the 113th element, 278113, are reviewed. Tow decay chains which are assigned to be ones originating from the isotope 277112 were observed in the 208Pb(70Zn, n) reaction. Both chains consisted of four consecutive alpha decays followed by a spontaneous fission. The results provide a confirmation of the production and decay of the isotope 277112 reported by a research group at Gesellschaft für Schwerionenforschung (GSI), Germany, produced via the same reaction by using a velocity filter. Tow decay chains, both consisted of four consecutive alpha decays followed by a spontaneous fission, were observed also in the reaction 209Bi(70Zn, n). Those are assigned to be the convincing candidate events of the decays of the isotope of the 113th element, 278113, and its daughter nuclei, 274Rg, 270Mt, 266Bh, and 262Db. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2007
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10. Experiments on synthesis of the heaviest elements at RIKEN.

Author

Morimoto, K., Morita, K., Kaji, D., Yoneda, A., Haba, H., Akiyama, T., Sato, N., Goto, S., Ideguchi, E., Katori, K., Kikunaga, H., Koura, H., Kudo, H., Ohnishi, T., Ozawa, A., Suda, T., Sueki, K., Tokanai, F., Yamaguchi, T., and Yoshida, A.

Subjects
*LINEAR accelerators, *PARTICLE accelerators, *PROTON accelerators, *ISOTOPES, *NUCLIDES
Abstract

In the Institute of Physical and Chemical Research (RIKEN), using high intensity heavy ion beams from the RIKEN Linear Accelerator, productions and decays of isotopes of the heaviest elements have been investigated by using the gas-filled recoil separator, GARIS. The isotopes studied were 265Hs, 271Ds, 272Rg, 277112, and 278113, respectively. Based on the observed decay chains consisting of consecutive alpha decays connected to the previously known alpha decays or spontaneous fissions, assignments of the initially produced isotopes were done. Our data with the atomic number from 108 to 112, agree well with the data previously taken. The production cross section of the isotope 278113 of the 113th element have reached around 32 fb which shows the simple decrease of the cross section with the increase of the atomic number. The isotopes were produced, for the first time in the In evaporation channel from heavy-ion induced fusion reaction. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2006
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11. High intensity target wheel at TASCA: target wheel control system and target monitoring.

Author

Jäger, E., Brand, H., Düllmann, Ch., Khuyagbaatar, J., Krier, J., Schädel, M., Torres, T., and Yakushev, A.

Subjects
*TARGETING (Nuclear strategy), *GAS-insulated cables, *RECOILLESS rifles, *SUPERHEAVY elements, *NUCLEAR fusion, *ACTINIDE elements
Abstract

At GSI Darmstadt, the gas-filled recoil separator transactinide separator and chemistry apparatus (TASCA) is in operation for experiments with superheavy elements. It is optimized for hot-fusion reactions with actinide targets. The small cross sections of such reactions require the capability to accept highest beam intensities. The limited availability of some of the exotic actinide isotopes limits the size of target systems. To maintain target integrity during long experiments, automated target monitoring and control is necessary. Here, the TASCA target wheel system and the on-line target monitoring are described. [ABSTRACT FROM AUTHOR]

Published
2014
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12. Absolute transmission and separation properties of the gas-filled recoil separator RITU

Author

Sarén, J., Uusitalo, J., Leino, M., and Sorri, J.

Subjects
*NUCLEAR fusion, *EVAPORATION (Chemistry), *PROBABILITY theory, *NEUTRONS, *EQUILIBRIUM, *NUCLEAR reactions, *QUADRUPOLES
Abstract

Abstract: The absolute transmission values of the RITU gas-filled recoil separator have been measured for several fusion evaporation products. Three different beams and several targets were used to create fusion evaporation residues in mass region A=170–190 mainly in neutron evaporation channels. Measured absolute transmission values from around 7% up to round about 90% have been observed for very asymmetric and symmetric reactions, respectively. For the reactions studied it was observed that the angular spread of products after the target and the angular acceptance of RITU determine the transmission probability relatively accurately. Magnetic rigidities and equilibrium charges of the product ions were seen to systemically decrease and increase, respectively, with increasing gas pressure. The comparison of observed equilibrium charges to various formulae is carried out. Clear minima of image width were found in case of asymmetric reactions as a function of gas pressure. Effects of the position of an additional movable beam stopper and the field strength of the first quadrupole magnet on transmission have been studied and are reported. [Copyright &y& Elsevier]

Published
2011
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13. Probing the limit of nuclear existence: Proton emission from 159Re

Author

Joss, D.T., Darby, I.G., Page, R.D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P.T., Jones, P.M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A.-P., Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A., and Cannon, A.J.

Subjects
*PARTICLES (Nuclear physics), *COLLISIONS (Nuclear physics), *NUCLEAR physics, *NUCLEAR reactions
Abstract

Abstract: The observation of the new nuclide 159 75Re84 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 106Cd(58Ni, ) and identified via its proton radioactivity using the ritu gas-filled separator and the great focal-plane spectrometer. Comparisons of the measured proton energy () and decay half-life () with values calculated using the WKB method indicate that the proton is emitted from an state. The implications of these results for future experimental investigations into even more proton unbound nuclei using in-flight separation techniques are considered. [Copyright &y& Elsevier]

Published
2006
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14. Status of heavy element research using a gas-filled recoil separator at RIKEN.

Author

Morita, Kosuke, Morimoto, Kouji, Kaji, Daiya, Zhao, Yu, Yoshida, Atsushi, Suda, Toshimi, Yoneda, Akira, Ohnishi, Tetsuya, Haba, Hiromitsu, Ideguchi, Eiji, Xu, Hu, Zheng, Tao, Kudo, Hisaaki, Sueki, Keisuke, Katori, Kenji, and Tanihata, Isao

Abstract

A gas-filled type of recoil separator for heavy element research was installed at an experimental hall of RIKEN Linear Accelerator facility to realize getting higher intensity of primary beam and long beam time. Performance of the separator was studied using target recoils and various nuclear reactions. The results show the high performance of the separator for heave element research. As an application of the GARIS, production and identification of an isotope of the 110th element 271[110] have been performed using the 208Pb(64Ni,1n)271[110] reaction. Three decay chains coincide well both in decay times and energies with the ones reported by the group of SHIP experiment at GSI, Germany. Our results provide a confirmation of the synthesis of an isotope 271[110] of element 110. [ABSTRACT FROM AUTHOR]

Published
2004
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15. Ion-optical design and multiparticle tracking in 3D magnetic field of the gas-filled recoil separator SHANS2 at CAFE2.

Author

Sheng, L.N., Hu, Q., Jia, H., Zhang, Z.Y., Chai, Z., Zhao, B., Zhang, Y., Gan, Z.G., He, Y., and Yang, J.C.

Subjects
*SUPERHEAVY elements, *MAGNETIC fields, *BEAM optics, *CHEMICAL properties, *PHYSICS
Abstract

The CAFE2 (China Accelerator Facility for superheavy Elements) is a new facility constructed at IMP-CAS (Institute of Modern Physics, Chinese Academy of Sciences). It is based on the upgrade of a superconducting linear accelerator. A new gas-filled recoil separator SHANS2 (Spectrometer for Heavy Atoms and Nuclear Structure-2) with a total flight length path of 5.85 m at the CAFE2 is designed to synthesize and study the superheavy elements, including their physical and chemical properties. The maximum acceptable divergence angles of the SHANS2 are ± 70 mrad and ± 113 mrad in horizontal and vertical directions, respectively, and the maximum magnetic rigidity is 2.5 Tm. The ion-optical design and simulation are investigated in detail, including the first and the fifth order beam optics. The magnets design and magnetic field calculation are presented. Using the 3D field maps, a multiparticle tracking study is carried out for the design validation, trajectory analysis, and performance evaluation. [ABSTRACT FROM AUTHOR]

Published
2021
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16. Beam intensity monitor based on gas scintillation emitted from helium gas molecules in a gas-filled recoil ion separator.

Author

Kaji, D., Morimoto, K., and Tokanai, F.

Subjects
*PARTICLE beams, *GAS scintillation detectors, *WAVELENGTHS, *HELIUM, *MOLECULES, *SEPARATION of gases, *MONOCHROMATORS
Abstract

Abstract: We have developed a new beam intensity monitor based on the gas scintillation emitted from helium gas molecules in a gas-filled recoil ion separator. The emission spectrum from the gas scintillation was measured using a monochromator over a wavelength range of 380–750nm. The emission strength as a function of the beam intensity was measured using a wavelength filter passing through the peak at 389nm. The emission strength was correlated as a function of the beam intensity within an intensity range of . [Copyright &y& Elsevier]

Published
2014
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17. -Decay branching ratios measured by -ray tagging

Author

Bianco, L., Page, R.D., Joss, D.T., Simpson, J., Cederwall, B., Gómez Hornillos, M.B., Greenlees, P.T., Hadinia, B., Jakobsson, U., Jones, P.M., Julin, R., Ketelhut, S., Labiche, M., Leino, M., Nyman, M., Paul, E.S., Petri, M., Peura, P., Puurunen, A., and Rahkila, P.

Subjects
*NUCLIDES, *SILICON diodes, *TARGETS (Nuclear physics), *BRANCHING ratios, *DECAY schemes (Radioactivity), *NUCLEAR reactions, *STATISTICAL correlation
Abstract

Abstract: The nuclides 168–170Pt were produced by bombarding isotopically enriched 92,94Mo targets with 336, 348MeV 78Kr ions. Prompt rays were detected at the target position and provided a selection criterion for the 168–170Pt nuclei. This technique enables the problem of the background from higher-energy decays in the spectrum to be circumvented. The Pt nuclei were separated in flight using the gas-filled separator RITU and implanted into the GREAT spectrometer, which was used to study subsequent decays. The -decay branching ratios of 164–166Os were deduced from the fraction of selected 168–170Pt nuclei correlated with decays of 164–166Os. The resulting branching ratios agree with the literature values but can have improved precision. [Copyright &y& Elsevier]

Published
2008
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18. The ion-optical design of the MARA recoil separator and absolute transmission measurements of the RITU gas-filled recoil separator

Author

Sarén, Jan

Subjects
ionit, recoil separator modelling, convolution, gas-filled recoil separator, ion optics, recoil separator, optiikka
Abstract

In this thesis work, the use of two complementary recoil separators for studies of nuclear structure via fusion-evaporation reactions are discussed. The design and the main ion-optical properties of the vacuum-mode recoil-mass separator MARA, intended for studies of nuclei with N Z close to the proton drip-line, are presented. MARA (Mass Analysing Recoil Apparatus) consists of a magnetic quadrupole triplet followed by an electrostatic de ector and a magnetic dipole. The working principle of MARA is discussed and the reasons for the choice of the optical parameters of the elements are given. The performance of MARA for di erent kind of fusion reactions has been studied with Monte Carlo simulations. The results of a sensitivity analysis especially of the electrostatic de ector are reported. The requirements for the instrumentation are discussed. The absolute transmission values of the RITU gas- lled recoil separator have been measured for several fusion evaporation products in the mass region A = 170{190 using di erent reaction asymmetries. It was observed that the angular distribution of products after the target and the angular acceptance of RITU determine the transmission value accurately. The e ects of lling-gas pressure on the average charge state and focal plane image properties as well as on transmission values have been studied experimentally. The transmission probability for 254No synthesized in the 48Ca+208Pb reaction has been calculated and is in agreement with the experiment. Simulations of transportation of 186Hg fusion products through RITU have been carried out. The simulated behaviour of transmission and image properties agrees well with an experiment.

Published
2011

19. Discovery of W-157 and Os-161

Author

Bianco, L, Page, RD, Darby, IG, Joss, DT, Simpson, J, Al-Khalili, JJ, Cannon, AJ, Cederwall, B, Eeckhaudt, S, Erturk, S, Gall, B, Hornillos, MBG, Grahn, T, Greenlees, PT, Hadinia, B, Heyde, Kristiaan, Jakobsson, U, Jones, PM, Julin, R, Juutinen, S, Ketelhut, S, Labiche, M, Leino, M, Leppanen, AP, Nyman, M, O'Donnell, D, Paul, ES, Petri, M, Peura, P, Puurunen, A, Rahkila, P, Ruotsalainen, P, Sandzelius, M, Sapple, PJ, Saren, J, Scholey, C, Smirnova, NA, Steer, AN, Stevenson, PD, Suckling, EB, Thomson, J, Uusitalo, J, Venhart, M, Scholey, Catherine -- 0000-0002-8743-6071, Stevenson, Paul -- 0000-0003-2645-2569, O'Donnell, David -- 0000-0002-4710-3803, Petri, Marina -- 0000-0002-3740-6106, Cederwall, Bo -- 0000-0003-1771-2656, Darby, Iain -- 0000-0003-2091-2616, Jones, Pete -- 0000-0001-7480-6603, Jakobsson, Ulrika -- 0000-0001-9741-141X, Gomez Hornillos -- 0000-0002-9282-9195, Grahn, Tuomas -- 0000-0002-6255-2279, Peura, Pauli -- 0000-0002-8541-0169, and [Bianco, L. -- Page, R. D. -- Darby, I. G. -- Joss, D. T. -- Grahn, T. -- Paul, E. S. -- Petri, M. -- Sapple, P. J. -- Thomson, J.] Univ Liverpool, Dept Phys, Liverpool L69 7ZE, Merseyside, England -- [Simpson, J. -- Hornillos, M. B. Gomez -- Labiche, M. -- O'Donnell, D.] STFC, Daresbury Lab, Warrington WA4 4AD, Cheshire, England -- [Al-Khalili, J. J. -- Cannon, A. J. -- Stevenson, P. D. -- Suckling, E. B.] Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England -- [Cederwall, B. -- Hadinia, B. -- Sandzelius, M.] Royal Inst Technol, Alba Nova Ctr, S-10691 Stockholm, Sweden -- [Eeckhaudt, S. -- Greenlees, P. T. -- Jakobsson, U. -- Jones, P. M. -- Julin, R. -- Juutinen, S. -- Ketelhut, S. -- Leino, M. -- Leppanen, A. -P. -- Nyman, M. -- Peura, P. -- Puurunen, A. -- Rahkila, P. -- Ruotsalainen, P. -- Saren, J. -- Scholey, C. -- Steer, A. N. -- Uusitalo, J. -- Venhart, M.] Univ Jyvaskyla, Dept Phys, FIN-40014 Jyvaskyla, Finland -- [Erturk, S.] Nigde Univ, Fen Edebiyat Fak, Fizik Bolumu, Nigde, Turkey -- [Gall, B.] ULP Strasbourg, IPHC, CNRS, IN2P3, F-67037 Strasbourg 2, France -- [Heyde, K.] Univ Ghent, Vakgrp Subatomaire Stralingsfysika, B-9000 Ghent, Belgium -- [Smirnova, N. A.] CEN Bordeaux Gradignan, F-33175 Gradignan, France

Subjects
Deduced neutron single-particle configurations in Os-161, W-157, Si detectors, NUCLEI, t(1/2), TOTAL DATA READOUT, Measured E alpha, t(1/2), Shell model calculations, NUCLEAR REACTIONS Ni-58+Cd-106 at 290, Physics and Astronomy, Measured E alpha, Deduced neutron single-particle configurations in Os-161, W-157, NEUTRON-DEFICIENT ISOTOPES, gas-filled recoil separator, PROTON DRIP-LINE, 310 MeV beam energy, NUCLEAR REACTIONS Ni-58+Cd-106 at 290, 300, 310 MeV beam energy, gas-filled recoil separator, Si detectors
Abstract

WOS: 000278933900003, The nuclides W-157 and Os-161 have been discovered ill reactions of Ni-58 ion beams with a Cd-106 target. The Os-161 alpha-decay energy and half-life were 6890 +/- 12 keV and 640 +/- 60 mu s. The daughter W-157 nuclei beta-decayed with a half-life of 275 +/- 40 ms, populating both low-lying alpha-decaying states in Ta-157, which is consistent with a 7/2(-) ground state in W-157. Fine structure observed in the alpha decay of Os-161 places the lowest excited state in W-157 with 1(pi) = 9/2(-) at 318 +/- 30 key. The branching ratio of 5.5(-2.2)(+3.1)% indicates that Os-161 also has a 7/2(-) ground state. Shell-model calculations analysing the effects of monopole shifts and a tensor force on the relative energies of 2f(7/2) and 1h(9/2) neutron states in N = 83 isotones are presented. (C) 2010 Elsevier B.V. All rights reserved., Jyvaskyla; United Kingdom Science and Technology Facilities Council; Swedish Natural Science Research Council; Academy of Finland [44875, 209430, 111965]; European Union [R113-CT-2004-506065, HPMT-CT-2001-00250]; Science and Technology Facilities Council [EP/C015266/1, EP/C015371/1, ST/G008671/1, ST/F012012/1, ST/J000108/1, EP/C543157/1, ST/G008620/1, ST/F012039/1], We thank the accelerator staff at Jyvaskyla for their excellent support and Paul Morrall from Daresbury Laboratory for making the targets. This work was supported by the United Kingdom Science and Technology Facilities Council; the Swedish Natural Science Research Council; the Academy of Finland through the Finnish Centre of Excellence Programme (project 44875 Nuclear and Condensed Matter Physics Programme at JYFL) and support for C.S. (contract 209430) and P.T.G. (contract 111965); the European Union Sixth Framework contract EURONS (R113-CT-2004-506065) and the European Union Marie Curie Programme (contract HPMT-CT-2001-00250).

Published
2010

20. Decays of new nuclides and isomers beyond the proton drip line - The influence of neutron configurations

Author

R. D. Page, L. Bianco, I. G. Darby, D. T. Joss, J. Simpson, J. S. Al-Khalili, A. J. Cannon, R. J. Cooper, S. Eeckhaudt, S. Ertürk, B. Gall, T. Grahn, P. T. Greenlees, B. Hadinia, P. M. Jones, D. S. Judson, R. Julin, S. Juutinen, S. Ketelhut, M. Labiche, M. Leino, A.-P. Leppänen, M. Nyman, D. O’Donnell, P. Rahkila, P. J. Sapple, J. Sarén, C. Scholey, A. N. Steer, P. D. Stevenson, E. B. Suckling, J. Thomson, J. Uusitalo, M. Venhart, Ismail Boztosun, A. B. Balantekin, 0-Belirlenecek, and Page, R.D., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Bianco, L., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Darby, I.G., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Joss, D.T., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Simpson, J., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Al-Khalili, J.S., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Cannon, A.J., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Cooper, R.J., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Eeckhaudt, S., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Ertürk, S., Nigde Universitesi, Fen-Edebiyat Falkultesi, Fizik Bdlumti, Nigde, Turkey -- Gall, B., IPHC, CNRS, IN2P3, ULP Strasbourg, 23 rue de Loess, Strasbourg, 67037, France -- Grahn, T., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Greenlees, P.T., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Hadinia, B., Royal Institute of Technology, Alba Nova Center, Stockholm, S-106 91, Sweden -- Jones, P.M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Judson, D.S., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Julin, R., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Juutinen, S., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Ketelhut, S., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Labiche, M., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Leino, M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Leppänen, A.-P., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Nyman, M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- O'Donnell, D., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Rahkila, P., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Sapple, P.J., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Sarén, J., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Scholey, C., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Steer, A.N., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Stevenson, P.D., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Suckling, E.B., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Thomson, J., Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Uusitalo, J., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland -- Venhart, M., Department of Physics, University of Jyvdskyld, Jyvdskyld, FIN-40014, Finland

Subjects
Physics, Proton, Gamma ray, Alpha particle, Segmented Si and Ge detectors. Measured E ? ,E proton ,E ? ,T 1/2, Nuclear physics, Nuclear Reactions 58 Ni+ 106 Cd at 290,300,310 MeV beam energy, Beta particle, Neutron, Enriched targets, Nuclide, Alpha decay, Gas-filled recoil separator, Atomic physics, Nuclear Experiment, Ground state
Abstract

Bozok University;Erciyes University;et al.;Istanbul University;Nigde University;The Turkish Atomic Energy Authority (TAEK), International Conference on Nuclear Physics and Astrophysics: From Stable Beams to Exotic Nuclei 2008 -- 25 June 2008 through 30 June 2008 -- -- 139817, The energy of the vh 9/2 orbital in nuclei above N = 82 drops rapidly in energy relative to the vf 7/2 orbital as the occupancy of the ?h 11/2 orbital increases. These two neutron orbitals become nearly degenerate as the proton drip line is approached. In this work, we have discovered the new nuclides 161 Os and 157 W, and studied the decays of the proton emitter 160 Re in detail. The 161 Os and 160 Re nuclei were produced in reactions of 290, 300 and 310 MeV 58 Ni ions with an isotopically enriched 106 Cd target, separated in-flight using the RITU separator and implanted into the GREAT spectrometer. The 161 Os a decays populated the new nuclide 157 W, which decayed by ß-particle emission. The ß decay fed the known ?-decaying l/2 + and 11/2 - states in 157 Ta, which is consistent with a vf 7/2 ground state in 157 W. The measured a-decay energy and half-life for 161 Os correspond to a reduced ?-decay width that is compatible with s-wave ?-particle emission, implying that its ground state is also a vf 7/2 state. Over 7000 160 Re nuclei were produced and the y decays of a new isomeric state feeding the ?d 3/2 level in 160 Re were discovered, but no evidence for the proton or a decay of the expected ?h 11/2 state could be found. The isomer decays offer a natural explanation for this non-observation and provides a striking example of the influence of the near degeneracy of the vh 9/2 and vf 7/2 orbitals on the properties of nuclei in this region. © 2008 American Institute of Physics., Academy of Finland Science and Technology Facilities Council Finnish Centre of Excellence in Atomic Layer Deposition Natural Sciences and Engineering Research Council of Canada, We would like to thank the technical staff at Jyvaskyla for their excellent support and to Paul Morrall from Daresbury Laboratory for making the targets. This work has been supported by the UK Science and Technology Facilities Council; the Swedish Natural Science Research Council; the Academy of Finland under the Finnish Centre of Excellence Programme (project 44875 Nuclear and Condensed Matter Physics Programme at JYFL); the European Union Sixth Framework contract EURONS (RII3-CT-2004-506065) and the European Union Marie Curie Programme (contract HPMT-CT-2001-00250).

Published
2008

21. Discovery of the proton emitting nucleus $^{159}$Re

Author

D. T. Joss, I. G. Darby, R. D. Page, J. Uusitalo, S. Eeckhaudt, T. Grahn, P. T. Greenlees, P. M. Jones, R. Julin, S. Juutinen, S. Ketelhut, M. Leino, A.-P. Leppänen, M. Nyman, J. Pakarinen, P. Rahkila, J. Sarén, C. Scholey, A. N. Steer, J. S. Al-Khalili, A. J. Cannon, P. D. Stevenson, S. Ertürk, B. Gall, B. Hadinia, M. Venhart, J. Simpson, Lídia S. Ferreira, Paramasivan Arumugan, Département Recherches Subatomiques (DRS-IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Lídia S. Ferreira, Paramasivan Arumugan, Joss, D.T., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom, STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom -- Darby, I.G., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Page, R.D., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Uusitalo, J., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Eeckhaudt, S., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Grahn, T., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Greenlees, P.T., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Jones, P.M., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Julin, R., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Juutinen, S., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Ketelhut, S., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Leino, M., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Leppänen, A.-P., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Nyman, M., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Pakarinen, J., Oliver Lodge Laboratory, University of Liverpool, Liverpool, L69 7ZE, United Kingdom -- Rahkila, P., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Sarén, J., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Scholey, C., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Steer, A.N., Department of Physics, University of Jyväskylä, PO Box 35, FIN-40014, Jyväskylä, Finland -- Al-Khalili, J.S., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Cannon, A.J., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Stevenson, P.D., Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom -- Ertürk, S., Nigde Universitesi, Fen-Edebiyat Falkültesi, Fizik Bölümü, Nigde, Turkey -- Gall, B., ULP Strasbourg, 23 rue du Loess, 67037 Strasbourg Cedex 2, France -- Hadinia, B., Department of Physics, Royal Institute of Technology, SE-10691, Stockholm, Sweden -- Venhart, M., Department of Nuclear Physics and Biophysics, Comenius University, Mlynska Dolina, 842 48, Bratislava 4, Slovakia -- Simpson, J., STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD, United Kingdom, and 0-Belirlenecek

Subjects
Si detectors, nuclear spin, Measured E p, Proton, Hadron, 02 engineering and technology, rhenium, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Nuclear physics, Isotopes of cadmium, 0202 electrical engineering, electronic engineering, information engineering, nuclei with mass number 150 to 189, Enriched targets, radioactive decay periods, Nuclide, Isotope, Chemistry, Nuclear structure, 020206 networking & telecommunications, T1/2, 13. Climate action, 020201 artificial intelligence & image processing, 23.50.+z, 27.70.+q, 21.10.Tg, 21.10.Hw, Gas-filled recoil separator, Nucleon, Radioactive decay, Nuclear reactions 58Ni + 106Cd at 300 MeV beam energy, proton emission decay
Abstract

Fund. para Cienc. Tecnol., FCT, Minist. Cienc. Tecnol.;Fundacao Calouste Gulbenkian;Fundacao Luso-Americana, International Conference on Proton Emitting Nuclei and Related Topics, PROCON 2007 -- 17 June 2007 through 23 June 2007 -- Lisbon, The observation of the new nuclide 159Re provides important insights into the evolution of single-particle structure in heavy nuclei beyond the proton drip line. The nuclide 159Re was synthesised in the reaction 106Cd(58Ni, 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 (Ep = 1805±20 keV) and decay half-life (t1/2 = 21±4 µs) with values calculated using the WKB method indicate that the proton is emitted from an h11/2 state. The implications of these results for future experimental investigations into even more proton unbound Re isotopes using in-flight separation techniques are considered. © 2007 American Institute of Physics.

Published
2007
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22. Discovery of the proton emitting nucleus Re-159

Author

Joss, D. T., Darby, I. G., Page, R. D., Uttsitalo, J., Eeckhaudt, S., Grahn, T., Nyman, A., Ferreira, LS, Arumugam, P, and 0-Belirlenecek

Subjects
measured Ep, t(1/2), NUCLEAR REACTIONS Ni-58+Cd-106 at 300 MeV beam energy, Si detectors, gas-filled recoil separator, enriched targets
Abstract

International Conference on Proton Emitting Nuclei and Related Topics -- JUN 17-23, 2007 -- Lisbon, PORTUGAL, WOS: 000252267300004, The 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., Fundacao Ciencia & Tecnol, Minist Ciencia & Tecnol, Fundacao Calouste Gulbenklan, Fundacao Luso Americana

Published
2007

23. Decay of the high-spin isomer in Re-160 : Changing single-particle structure beyond the proton drip line

Author

Darby, I. G., Page, R. D., Joss, D. T., Simpson, J., Bianco, L., Cooper, R. J., Eeckhaudt, S., Erturk, S., Gall, B., Grahn, T., Greenlees, P. T., Hadinia, Baharak, Jones, P. M., Judson, D. S., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppanen, A. -P, Nyman, M., Rahkila, P., Saren, J., Scholey, C., Steer, A. N., Uusitalo, J., Venhart, M., Darby, I. G., Page, R. D., Joss, D. T., Simpson, J., Bianco, L., Cooper, R. J., Eeckhaudt, S., Erturk, S., Gall, B., Grahn, T., Greenlees, P. T., Hadinia, Baharak, Jones, P. M., Judson, D. S., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppanen, A. -P, Nyman, M., Rahkila, P., Saren, J., Scholey, C., Steer, A. N., Uusitalo, J., and Venhart, M.

Abstract

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., QC 20120822

Published
2011
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24. Discovery of W-157 and Os-161

Author

Bianco, L., Page, R. D., Darby, I. G., Joss, D. T., Simpson, J., Al-Khalili, J. J., Cannon, A. J., Cederwall, Bo, Eeckhaudt, S., Erturk, S., Gall, B., Hornillos, M. B. Gomez, Grahn, T., Greenlees, P. T., Hadinia, Baharak, Heyde, K., Jakobsson, U., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Labiche, M., Leino, M., Leppanen, A. -P, Nyman, M., O'Donnell, D., Paul, E. S., Petri, M., Peura, P., Puurunen, A., Rahkila, P., Ruotsalainen, P., Sandzelius, Mikael, Sapple, P. J., Saren, J., Scholey, C., Smirnova, N. A., Steer, A. N., Stevenson, P. D., Suckling, E. B., Thomson, J., Uusitalo, J., Venhart, M., Bianco, L., Page, R. D., Darby, I. G., Joss, D. T., Simpson, J., Al-Khalili, J. J., Cannon, A. J., Cederwall, Bo, Eeckhaudt, S., Erturk, S., Gall, B., Hornillos, M. B. Gomez, Grahn, T., Greenlees, P. T., Hadinia, Baharak, Heyde, K., Jakobsson, U., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Labiche, M., Leino, M., Leppanen, A. -P, Nyman, M., O'Donnell, D., Paul, E. S., Petri, M., Peura, P., Puurunen, A., Rahkila, P., Ruotsalainen, P., Sandzelius, Mikael, Sapple, P. J., Saren, J., Scholey, C., Smirnova, N. A., Steer, A. N., Stevenson, P. D., Suckling, E. B., Thomson, J., Uusitalo, J., and Venhart, M.

Abstract

The nuclides W-157 and Os-161 have been discovered ill reactions of Ni-58 ion beams with a Cd-106 target. The Os-161 alpha-decay energy and half-life were 6890 +/- 12 keV and 640 +/- 60 mu s. The daughter W-157 nuclei beta-decayed with a half-life of 275 +/- 40 ms, populating both low-lying alpha-decaying states in Ta-157, which is consistent with a 7/2(-) ground state in W-157. Fine structure observed in the alpha decay of Os-161 places the lowest excited state in W-157 with 1(pi) = 9/2(-) at 318 +/- 30 key. The branching ratio of 5.5(-2.2)(+3.1)% indicates that Os-161 also has a 7/2(-) ground state. Shell-model calculations analysing the effects of monopole shifts and a tensor force on the relative energies of 2f(7/2) and 1h(9/2) neutron states in N = 83 isotones are presented. (C) 2010 Elsevier B.V. All rights reserved., QC 20101213

Published
2010
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25. alpha-Decay branching ratios measured by gamma-ray tagging

Author

Bianco, L., Page, R. D., Joss, D. T., Simpson, J., Cederwall, Bo, Hornillos, M. B. G., Greenlees, P. T., Hadinia, B., Jakobsson, U., Jones, P. M., et al, Bianco, L., Page, R. D., Joss, D. T., Simpson, J., Cederwall, Bo, Hornillos, M. B. G., Greenlees, P. T., Hadinia, B., Jakobsson, U., Jones, P. M., and et al

Abstract

The nuclides Pt168-170 were produced by bombarding isotopically enriched Mo-92,Mo-94 targets with 336, 348 MeV Kr-78 ions. Prompt gamma rays were detected at the target position and provided a selection criterion for the Pt168-170 nuclei. This technique enables the problem of the background from higher-energy alpha decays in the spectrum to be circumvented. The Pt nuclei were separated in flight using the gas-filled separator RITU and implanted into the GREAT spectrometer, which was used to study subsequent alpha decays. The alpha-decay branching ratios of Os164-166 were deduced from the fraction of selected Pt168-170 nuclei correlated with a decays Of Os164-166. The resulting branching ratios agree with the literature values but can have improved precision., QC 20100525

Published
2008
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26. Discovery of the proton emitting nucleus 159Re

Author

Joss, D. T., Darby, I. G., Page, R. D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A. -P, Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A. N., Al-Khalili, J. S., Cannon, A. J., Stevenson, P. D., Ertürk, S., Gall, B., Hadinia, Baharak, Venhart, M., Simpson, J., Joss, D. T., Darby, I. G., Page, R. D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A. -P, Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A. N., Al-Khalili, J. S., Cannon, A. J., Stevenson, P. D., Ertürk, S., Gall, B., Hadinia, Baharak, Venhart, M., and Simpson, J.

Abstract

The observation of the new nuclide 159Re provides important insights into the evolution of single-particle structure in heavy nuclei beyond the proton drip line. The nuclide 159Re was synthesised in the reaction 106Cd(58Ni, 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 (Ep = 1805±20 keV) and decay half-life (t1/2 = 21±4 μs) with values calculated using the WKB method indicate that the proton is emitted from an h11/2 state. The implications of these results for future experimental investigations into even more proton unbound Re isotopes using in-flight separation techniques are considered., QC 20141103

Published
2007
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27. Probing the limit of nuclear existence : Proton emission from Re-159

Author

Joss, D. T., Darby, I. G., Page, R. D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A. -P, Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A., Cannon, A. J., Stevenson, P. D., Al-Khalili, J. S., Ertürk, S., Venhart, M., Gall, B., Hadinia, Baharak, Simpson, J., Joss, D. T., Darby, I. G., Page, R. D., Uusitalo, J., Eeckhaudt, S., Grahn, T., Greenlees, P. T., Jones, P. M., Julin, R., Juutinen, S., Ketelhut, S., Leino, M., Leppänen, A. -P, Nyman, M., Pakarinen, J., Rahkila, P., Sarén, J., Scholey, C., Steer, A., Cannon, A. J., Stevenson, P. D., Al-Khalili, J. S., Ertürk, S., Venhart, M., Gall, B., Hadinia, Baharak, and Simpson, J.

Abstract

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., QC 20110812

Published
2006
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