| 1. |
- Schlegel, C, et al.
(författare)
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K-isomers in very neutron-rich nuclei around mass 180
- 2000
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Ingår i: Physica Scripta. Topical Issues. - 0281-1847. ; T88, s. 72-76
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Tidskriftsartikel (refereegranskat)abstract
- gamma-spectroscopy methods have been used to search for microsecond isomers among the fragmentation products of a 1 GeV/nucleon Pb-208 beam. In particular the population of the known K-pi = 35/2(-) isomer in W-179 has been investigated and several new isomeric decays have been found for neutron rich nuclei in the A approximate to 180-200 mass region. The ground state band of the neutron rich N = 116 system of W-190 has been identified for the first time and we discuss its structure in comparison to neighboring systems.
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| 2. |
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| 3. |
- Mineva, AN, et al.
(författare)
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A new mu s isomer in Sb-136 produced in the projectile fission of U-238
- 2001
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Ingår i: EUROPEAN PHYSICAL JOURNAL A. - : SPRINGER-VERLAG. - 1434-6001. ; 11:1, s. 9-13
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Tidskriftsartikel (refereegranskat)abstract
- The neutron-rich isotope Sb-136 has been produced following the relativistic projectile fission of U-238 in an experiment performed at the Fragment Separator at GSI, Darmstadt. Delayed gamma -ray spectroscopy of the fission products has been performed aft
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| 4. |
- Mineva, Milena, et al.
(författare)
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A New us Isomer in 136Sb Produced in the Projectile Fission of 238U
- 2001
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Ingår i: European Physical Journal A. Hadrons and Nuclei. - 1434-6001. ; 11, s. 9-13
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Tidskriftsartikel (refereegranskat)abstract
- The neutron-rich isotope Sb-136 has been produced following the relativistic projectile fission of U-238 in an experiment performed at the Fragment Separator at GSI, Darmstadt. Delayed gamma -ray spectroscopy of the fission products has been performed after isotope separation. A new isomeric state in Sb-136 has been populated, and its lifetime measured as T-1/2 = 565(50) ns. Realistic and empirical shell-model calculations have been performed and are compared to the experimental observables.
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| 5. |
- Podolyak, Z, et al.
(författare)
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Isomer spectroscopy of neutron rich W-190(116)
- 2000
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Ingår i: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 491:3-4, s. 225-231
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Gamma-rays de-exciting a millisecond isomer in the neutron-rich nucleus W-190(74)116 have been observed following relativistic projectile fragmentation of a I GeV per nucleon Pb-208 beam. Th, isomeric decay populates the ground-state rotational band, with
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| 6. |
- Schlegel, C, et al.
(författare)
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K-isomers in very neutron-rich nuclei around mass 180
- 2000
-
Ingår i: PHYSICA SCRIPTA. - : ROYAL SWEDISH ACAD SCIENCES. - 0281-1847. ; T88, s. 72-76
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- gamma-spectroscopy methods have been used to search for microsecond isomers among the fragmentation products of a 1 GeV/nucleon Pb-208 beam. In particular the population of the known K-pi = 35/2(-) isomer in W-179 has been investigated and several new iso
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| 7. |
- Aleksandrov, D., et al.
(författare)
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Halo excitations in fragmentation of He-6 at 240 MeV/u on carbon and lead targets
- 2000
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Ingår i: Nuclear Physics A. - 0375-9474. ; 669:1-2, s. 51-64
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Tidskriftsartikel (refereegranskat)abstract
- Dissociation of a 240 MeV/u beam of He-6, incident on carbon and lead targets, has been studied in kinematically complete experiments to investigate low-lying excitation modes in the halo nucleus He-6. It is shown that alignment effects characterize the inelastic scattering and allow an unambiguous assignment of the spin of a narrow resonance observed in the excitation energy spectrum. The differential cross sections for the He-6 inelastic scattering on carbon and lead targets were deduced from the measured moments of the two neutrons and the a-particle. An analysis of these distributions shows that quadrupole and, possibly, monopole excitations characterize the hadronic interaction, while the dipole mode is dominating in Coulomb dissociation. Neither theoretically predicted new resonance states in He-6 nor nuclear excitation of a dipole mode were found. Direct evidence has been obtained for strong suppression of Coulornb post-acceleration in direct Coulomb breakup in a lead target.
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| 8. |
- Markenroth, Karin, 1973, et al.
(författare)
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He-8-He-6: a comparative study of nuclear fragmentation reactions
- 2001
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Ingår i: Nuclear Physics A. - 0375-9474. ; 679:3-4, s. 462-480
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Tidskriftsartikel (refereegranskat)abstract
- Dissociation of 227 MeV/u He-8 in a carbon target has been studied in kinematically complete experiments. The data include the relative energy spectrum, angular distributions in the neutron knock-out channel (He-6 + n) as well as diffractive dissociation and inelastic scattering into the (He-6 + 2n) channel. The data are compared with corresponding results from the well-known halo nucleus He-6. In both cases it is found that neutron knock-out is the: dominating reaction channel. The relative energy spectrum (He-6 + n) shows a structure, which is interpreted as being due to the I-pi = 3/2(-) resonance in the He-7 ground state with about equal contribution from its I-pi = 1/2(-) spin-orbit partner. The He-7 resonance shows a spin alignment similar to that observed in He-5, but with a smaller anisotropy indicating that the structure of the He-8 ground state is more complicated than that of He-6. The data in the (He-6 + 2n) channel were used to identify resonances in the excitation energy spectrum of He-8. If the spectrum is interpreted as two overlapping resonances, the spin-parity assignment for these is found to be 2(+) and 1(-), respectively.
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| 9. |
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| 10. |
- Podolyak, Z, et al.
(författare)
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Isomeric decays in neutron-rich W, Os and Pt nuclei
- 2002
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Ingår i: Progress of Theoretical Physics. Supplement. - 0375-9687. ; :146, s. 467-472
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Tidskriftsartikel (refereegranskat)abstract
- Relativistic energy fragmentation of a 1 GeV/nucleon Pb-208 beam was used to populate a wide range of nuclei on both sides of the valley of beta-stability. The structure of these nuclei was studied by the identification of discrete gamma-ray transitions depopulating isomeric states with lifetimes in the nano- to millisecond range. Highlights of the experiment include the first observation of gamma-ray transitions in the neutron-rich nuclei (188)TA, W-190, Re-192, Os-195, Ir-197,Ir-198, Pt-201,Pt-202. The yrast states in W-190 and Pt-202 as well as the decay out from 10-20 ns isomers in Pt-202,Pt-201 and Os-195 are discussed. The observation of the previously reported isomeric K = 35/2 states in Hf-175, W-179 and Re-181 represents the highest discrete spin states observed to date following a projectile fragmentation reaction.
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