| 1. |
- Andreyev, A. N., et al.
(författare)
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Shape-changing particle decays of Bi-185 and structure of the lightest odd-mass Bi isotopes
- 2004
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 69:5, s. 054308-
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Tidskriftsartikel (refereegranskat)abstract
- Proton and alpha decay of the proton-rich nuclide Bi-185 has been restudied in more detail in the complete fusion reaction Nb-93(Mo-95, 3n)Bi-185 at the velocity filter SHIP. The observed decay pattern of Bi-185 and of the heavier odd-mass isotopes Bi-187,Bi-189,Bi-191,Bi-193 are interpreted based on potential-energy surface calculations. It is shown that the experimental systematics of the particle decays and of the excited states in these nuclei (where known) can be explained by the prolate-oblate shape co-existence at low excitation energy. The observed state in Bi-185 is proposed to be of prolate nature, which is in contrast with the previously proposed oblate interpretation.
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| 2. |
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| 3. |
- Van De Vel, K., et al.
(författare)
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In-beam gamma-ray spectroscopy of Po-190 : First observation of a low-lying prolate band in Po isotopes
- 2003
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 17:2, s. 167-171
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Tidskriftsartikel (refereegranskat)abstract
- Gamma rays from excited states of Po-190 have been observed using I the Jurosphere Ge-detector array coupled to the RITU gas-filled separator. They were associated with a collective band which from spin 4h onwards resembles the prolate rotational bands known in the isotones Pb-188 and Hg-186. This indicates that in Po-190 the prolate configuration becomes yrast above I = 2h. The experimental results are interpreted in a two-band mixing calculation and are in agreement with a-decay data and potential energy surface calculations.
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| 4. |
- Andreyev, A. N., et al.
(författare)
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The discovery of a prolate-oblate-spherical shape triple of spin 0(+) states in the atomic nucleus Pb-186
- 2001
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 682, s. 482C-486C
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Tidskriftsartikel (refereegranskat)abstract
- Two excited J(pi)=0(+) states in Pb-186 populated in the a-decay of Po-190 have been identified through alpha -particle/conversion electron coincidences in an experiment at the velocity filter SHIP. The parent Po-190 nuclei have been produced in the Nd-142(Cr-52,4n)Po-190 complete fusion reaction, alpha -particle energies and branching ratios have been measured and hindrance factors were deduced. The observed states have been interpreted as the band heads of the known prolate and (yet unobserved) oblate rotational bands in Pb-186.
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| 5. |
- Gladnishki, KA, et al.
(författare)
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Angular Momentum Population in the Projectile Fragmentation of 238U at 750 MeV/nucleon
- 2004
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 69:2
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Tidskriftsartikel (refereegranskat)abstract
- A systematic study of the population probabilities of nanosecond and microsecond isomers produced following the projectile fragmentation of U-238 at 750 MeV/nucleon has been undertaken at the SIS/FRS facility at GSI. Approximately 15 isomeric states in neutron-deficient nuclei around A similar to 190 were identified and the corresponding. isomeric ratios determined. The results are compared with a model based on the statistical abrasion-ablation description of relativistic fragmentation and simple assumptions concerning gamma cascades in the final nucleus (sharp cutoff). This model represents an upper limit for the population of isomeric states in relativistic projectile fragmentation. When the decay properties of the states above the isomer are taken into account, as opposed to the sharp cutoff approximation, a good agreement between the experimental and calculated angular momentum population is obtained.
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| 6. |
- Gladnishki, KA, et al.
(författare)
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Isomer spectroscopy in the neutron-deficient lead region following projectile fragmentation
- 2003
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Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254. ; 34:4, s. 2395-2398
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Tidskriftsartikel (refereegranskat)abstract
- Projectile fragmentation of a 750 MeV/nucleon U-238 beam was used to populate neutron-deficient nuclei around A similar to190. Isomeric states in Hg, Tl, Pb, Bi, and Po isotopes were identified and their lifetimes determined, with the ultimate aim of measuring their isomeric ratios to provide information on the spin population in such reactions.
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| 7. |
- Joss, D. T., et al.
(författare)
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Identification of excited states in Os-167 and Os-168 : shape coexistence at extreme neutron deficiency
- 2001
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Ingår i: Nuclear Physics A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 689:04-mar, s. 631-654
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Tidskriftsartikel (refereegranskat)abstract
- Excited states in the very neutron-deficient isotopes Os-167 and Os-168 have been observed using the reaction Sn-112(Ni-58, 2pxn). The JUROSPHERE gamma -ray spectrometer array was used in conjunction with the RITU gas-filled recoil separator to collect prompt gamma radiation in coincidence with recoils implanted in a silicon strip detector located at the focal plane of RITU. Using a selective recoil decay tagging technique it has been possible to unambiguously assign gamma -ray transitions to Os-167 and Os-168 through the characteristic a radioactivity of these nuclides. The high-spin structure of the bands is discussed in terms of quasiparticle configurations within the framework of the cranked shell model. The role of shape coexistence in Os-168 is examined with phenomenological three-band mixing calculations.
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| 8. |
- Joss, D. T., et al.
(författare)
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Strongly coupled bands in the neutron-deficient nucleus Re-167
- 2003
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Ingår i: Physical Review C. Nuclear Physics. - : American Physical Society. - 0556-2813 .- 1089-490X. ; 68:1
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Tidskriftsartikel (refereegranskat)abstract
- Excited states in the neutron-deficient nucleus Re-167 have been observed in a recoil-tagging experiment performed with the Jurosphere gamma-ray spectrometer in conjunction with the RITU gas-filled recoil separator. The low-spin yrast band, based on a proton h(11/2) orbital, comprises a strongly coupled band and exhibits significant signature splitting, indicative of a triaxial shape with gamma<0degrees. At higher spin the rotational alignment of a pair of i(13/2) neutrons induces a transition to an axial prolate shape resulting in a drastic reduction of the signature splitting. Two other strongly coupled bands have been established and their structures are discussed in terms of quasiparticle configurations.
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| 9. |
- Joss, D. T., et al.
(författare)
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Yrast spectroscopy in the neutron-deficient nucleus Os-169
- 2002
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Ingår i: Physical Review C. Nuclear Physics. - : American Physical Society. - 0556-2813 .- 1089-490X. ; 66:5
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Tidskriftsartikel (refereegranskat)abstract
- Excited states in the neutron-deficient isotope Os-169 have been identified for the first time in an experiment using the Jurosphere gamma-ray spectrometer in conjunction with the Ritu gas-filled recoil separator. The problems associated with identifying neutron-deficient isotopes produced with low fusion cross sections against a high background of competing channels, including fission, have been overcome by using the recoil-decay tagging technique. The band structures observed in Os-169 are interpreted in the context of the systematics of neighboring nuclei and the predictions of cranked Woods-Saxon calculations. The systematics of the second (i(13/2))(2) neutron alignment in this region are discussed.
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| 10. |
- Shor-Posner, G., et al.
(författare)
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Quality of life measures in the Miami HIV-1 infected drug abusers cohort : Relationship to gender and disease status
- 2000
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Ingår i: Journal of Substance Abuse. - : Elsevier. - 0899-3289 .- 1873-6491. ; 11:4, s. 395-404
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This study examined activity, daily living, health, support, and outlook in HIV+ drug users. Methods: Using the physician-administered Spitzer Index, the study assessed 75 HIV-1 seropositive men (n = 51) and women (n = 24) enrolled in the Miami HIV-1 Infected Drug Abusers Study (MIDAS). Results: Total composite scores were significantly lower in the HIV-1 infected women than the men (p = .03). Significant gender differences were observed in activity assessment, independent of disease status, with women six times as likely to have lower activity scores (p = .0038). Most women (45%) in this category were homeless or marginally housed, compared to II percent of the men. Additionally, women with low activity scores had less social support than women with high activity scares. Cocaine use was significantly related to reports of normal activity, and varied across genders; more men used cocaine than women (p = .03). Conylared to non-AIDS participants, AIDS patients were more likely to have lower scores in health (p = .009) and poorer outlook (p = .03). Implications: These findings reveal specific deficits in areas of psychosocial capacity particularly in HIV-1 infected women who abuse drugs, that may need to be strengthened in order to enhance function and adherence to treatment, as well as well-being.
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