| 1. |
- Benlliure, J., et al.
(författare)
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New experimental approaches to investigate the fission dynamics
- 2016
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Ingår i: AIP Conference Proceedings. - : Author(s). - 1551-7616 .- 0094-243X. - 9780735414112 ; 1753
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Konferensbidrag (refereegranskat)abstract
- The first ever achieved full identification of both fission fragments, in atomic and mass number, made it possible to define new observables sensitive to the fission dynamics along the fission path up to the scission point. Moreover, proton-induced fission of 208Pb at high energies offers optimal conditions for the investigation of dissipative, and transient effects, because of the high-excitation energy of the fissioning nuclei, its low angular momentum, and limited shape distortion by the reaction. In this work we show that the charge distribution of the final fission fragments can constrain the ground-to-saddle dynamics while the mass distribution is sensitive to the dynamics until the scission point.
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| 2. |
- Chatillon, A., et al.
(författare)
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Accurate measurements of fission-fragment yields in U-234,U-235,U-236,U-238(gamma,f) with the SOFIA set-up
- 2016
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Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9782759819706 ; 111
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Konferensbidrag (refereegranskat)abstract
- SOFIA (Studies On Fission with Aladin) is a new experimental set-up dedicated to accurate measurement of fission-fragments isotopic yields. It is located at GSI, the only place to use inverse kinematics at relativistic energies in order to study the (gamma,f) electromagnetic-induced fission. The SOFIA set-up is a large-acceptance magnetic spectrometer, which allows to fully identify both fission fragments in coincidence on the whole fission-fragment range. This paper will report on fission yields obtained in U-234,U-235,U-236,U-238(gamma,f) reactions.
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| 3. |
- Grente, L., et al.
(författare)
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The SOFIA experiment: Measurement of 236U fission fragment yields in inverse kinematics
- 2016
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Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 122:01006
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Konferensbidrag (refereegranskat)abstract
- The SOFIA (Studies On FIssion with Aladin) experiment aims at measuring fission-fragments isotopic yields with high accuracy using inverse kinematics at relativistic energies. This experimental technique allows to fully identify the fission fragments in nuclear charge and mass number, thus providing very accurate isotopic yields for low energy fission of a large variety of fissioning systems. This report focuses on the latest results obtained with this set-up concerning electromagnetic-induced fission of 236U.
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| 4. |
- Rodriguez-Sanchez, J. L., et al.
(författare)
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Dissipative effects in fission investigated with proton-on-lead reactions
- 2016
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Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9788874381012 ; 117, s. Art. no. 08017-
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Konferensbidrag (refereegranskat)abstract
- The complete kinematic measurement of the two fission fragments permitted us to investigate dissipative effects at large deformations, between the saddle-point and the corresponding scission configurations. Up to now, this kind of study has only been performed with fusionfission reactions using a limited number of observables, such as the mass distribution of the fission fragments or the neutron multiplicities. However, the large angular momenta gained by the compound nucleus could affect the conclusions drawn from such experiments. In this work, the use of spallation reactions, where the fissioning systems are produced with low angular momentum, small deformations and high excitation energies, favors the study of dissipation, and allowed us to define new observables, such as postscission neutron multiplicities and the neutron excess of the final fission fragments as a function of the atomic number of the fissioning system. These new observables are used to investigate the dissipation at large deformations.
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| 5. |
- Rodriguez-Sanchez, J. L., et al.
(författare)
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Light charged particles emitted in fission reactions induced by protons on Pb-208
- 2016
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Ingår i: Physical Review C. - 2469-9985 .- 2469-9993. ; 94:3
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Tidskriftsartikel (refereegranskat)abstract
- Light charged particles emitted in proton-induced fission reactions on Pb-208 have been measured at different kinetic energies: 370A, 500A, and 650A MeV. The experiment was performed by the SOFIA Collaboration at the GSI facilities in Darmstadt (Germany). The inverse kinematics technique was combined with a setup especially designed to measure light charged particles in coincidence with fission fragments. This measurement allowed us, for the first time, to obtain correlations between the light charged particles emitted during the fission process and the charge distributions of the fission fragments. These correlations were compared with different model calculations to assess the ground-to-saddle dynamics. The results confirm that transient and dissipative effects are required for an accurate description of the fission observables.
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| 6. |
- Rodriguez-Sanchez, J. L., et al.
(författare)
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Presaddle and postsaddle dissipative effects in fission using complete kinematics measurements
- 2016
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Ingår i: Physical Review C. - 2469-9985 .- 2469-9993. ; 94:6
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Tidskriftsartikel (refereegranskat)abstract
- A complete kinematics measurement of the two fission fragments was used for the first time to investigate fission dynamics at small and large deformations. Fissioning systems with high excitation energies, compact shapes, and low angular momenta were produced in inverse kinematics by using spallation reactions of lead projectiles. A new generation experimental setup allowed for the first full and unambiguous identification in mass and atomic number of both fission fragments. This measurement permitted us to accurately determine fission cross sections, the charge distribution, and the neutron excess of the fission fragments as a function of the atomic number of the fissioning system. These data are compared with different model calculations to extract information on the value of the dissipation parameter at small and large deformations. The present results do not show any sizable dependence of the nuclear dissipation parameter on temperature or deformation.
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