| 1. |
- de Walle, J. V., et al.
(författare)
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Coulomb excitation of the N=50 nucleus Zn-80
- 2008
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Ingår i: AIP Conference Proceedings. - 1551-7616 .- 0094-243X. ; 1012, s. 291-295 453
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Konferensbidrag (refereegranskat)abstract
- Neutron rich Zinc isotopes, including the N=50 nucleus Zn-80, were produced and post-accelerated at the Radioactive Ion Beam (RIB) facility REX-ISOLDE (CERN). Low-energy Coulomb excitation was induced on these isotopes after post-acceleration, yielding B(E2) strengths to the first excited 2(+) states. For the first time, an excited state in Zn-80 was observed and the 2(1)(+) state in Zn-78 was established. The measured B(E2,2(1)(+) -> 0(1)(+)) values are compared to two sets of large scale shell model calculations. Both calculations reproduce the observed B(E2) systematics for the full Zinc isotopic chain. The results for N=50 isotones indicate a good N=50 shell closure and a strong Z=28 proton core polarization. The new results serve as benchmarks to establish theoretical models, predicting the nuclear properties of the doubly magic nucleus Ni-78.
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| 2. |
- Kröll, Th, et al.
(författare)
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Quadrupole Collectivity of neutron-rich nuclei around 132Sn
- 2008
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Ingår i: Frontiers in Nuclear Structure, Astrophysics, and Reactions, FINUSTAR 2007. - : AIP. - 9780735405325 ; 1012, s. 296-299
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Konferensbidrag (refereegranskat)abstract
- We report on the "safe" Coulomb excitation of neutron-rich Cd, Xe, and Ba isotopes in the vicinity of the doubly-magic nucleus 132Sn. The radioactive nuclei have been produced by ISOLDE at CERN and postaccelerated by the REX-ISOLDE facility. The γ-decay of excited states has been detected by the MINIBALL array. The presented preliminary results for the B(E2) values are consistent with expectations from phenomenological systematics and will be compared with theoretical calculations.
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| 3. |
- Ekström, Andreas, et al.
(författare)
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Coulomb excitation of Sn-110 using REX-ISOLDE
- 2006
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Ingår i: Physica Scripta. - 1402-4896 .- 0031-8949. ; T125, s. 190-191
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Konferensbidrag (refereegranskat)abstract
- In this paper, we report the preliminary result from the first Coulomb excitation experiment at REX-ISOLDE (Habs et al 1998 Nucl. Instrum. Methods B 139 128) using neutron-deficient Sn-beams. The motivation of the experiment is to deduce the reduced transition probability, B(E2; 2(+) -> 0(+)), for the sequence of neutron deficient, unstable, even-even Sn- isotopes from Sn-110 to ultimately Sn-110. Safe Coulomb excitation using a radioactive beam opens up a new path to study the lifetime of the first excited 2(+) state in these isotopes. The de-excitation path following fusion-evaporation reactions will for the even-even Sn isotopes pass via an isomeric 6(+) state, located at higher energy, which thus hampers measurements of the lifetime of the first excited state using, e. g., recoil-distance methods. For this reason the reduced transition probability of the first excited 2(+) state has remained unknown in this chain of isotopes although the B(E2) value of the stable isotope Sn-112 was measured approximately 30 years ago (see, e. g., Stelson et al 1970 Phys. Rev. C 2 2015). Our experiment is thus the first to accomplish a measurement of this quantity in Sn-110. It is believed that the determination of the B(E2) value in Sn-110 will indicate the turnover point from a trend of increasing B(E2) values for the heavier isotopes to a trend characterized by less collectivity. Our first preliminary result indicates that this assumption may well be correct.
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| 4. |
- Cederkäll, Joakim, et al.
(författare)
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REX-ISOLDE - experiences from the first year of operation
- 2004
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 746, s. 17-17
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Konferensbidrag (refereegranskat)abstract
- The Radioactive beam EXperiment (REX) at CERN-ISOLDE has been commissioned and the first experiments successfully completed during 2002 and 2003. The concept used for post-acceleration has proven to be flexible and the experimental program has therefore been extended during the past year. This paper relays some experiences drawn from using the machine in the current program and also conveys some plans for the future.
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| 5. |
- Kester, O., et al.
(författare)
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Accelerated radioactive beams from REX-ISOLDE
- 2003
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Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 204, s. 20-20
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Konferensbidrag (refereegranskat)abstract
- In 2001 the linear accelerator of the Radioactive beam EXperiment (REX-ISOLDE) delivered for the first time accelerated radioactive ion beams, at a beam energy of 2 MeV/u. REX-ISOLDE uses the method of charge-state breeding, in order to enhance the charge state of the ions before injection into the LINAC. Radioactive singly-charged ions from the on-line mass separator ISOLDE are first accumulated in a Penning trap, then charge bred to an A/q
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| 6. |
- Scheit, H., et al.
(författare)
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Coulomb excitation of neutron-rich beams at REX-ISOLDE
- 2005
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-601X .- 1434-6001. ; 25:Suppl. 1, s. 397-402
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Konferensbidrag (refereegranskat)abstract
- After the successful commissioning of the radioactive beam experiment at ISOLDE (REX-ISOLDE) - an accelerator for exotic nuclei produced by ISOLDE - in 2002 and the promotion to a CERN user facility in 2003, first physics experiments using these beams were performed. Initial experiments focused on the region of deformation in the vicinity of the neutron-rich Na and Mg isotopes. Preliminary results on the neutron-rich Na and Mg isotopes show the high potential and physics opportunities offered by the exotic isotope accelerator REX in conjunction with the modern Germanium gamma spectrometer MINIBALL.
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