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117 results on '"F. Farget"'

1. Cross-shell states in 15C: A test for p-sd interactions

Author: J. Lois-Fuentes, B. Fernández-Domínguez, X. Pereira-López, F. Delaunay, W.N. Catford, A. Matta, N.A. Orr, T. Duguet, T. Otsuka, V. Somà, O. Sorlin, T. Suzuki, N.L. Achouri, M. Assié, S. Bailey, B. Bastin, Y. Blumenfeld, R. Borcea, M. Caamaño, L. Caceres, E. Clément, A. Corsi, N. Curtis, Q. Deshayes, F. Farget, M. Fisichella, G. de France, S. Franchoo, M. Freer, J. Gibelin, A. Gillibert, G.F. Grinyer, F. Hammache, O. Kamalou, A. Knapton, Tz. Kokalova, V. Lapoux, B. Le Crom, S. Leblond, F.M. Marqués, P. Morfouace, J. Pancin, L. Perrot, J. Piot, E. Pollacco, D. Ramos, D. Regueira-Castro, C. Rodríguez-Tajes, T. Roger, F. Rotaru, M. Sénoville, N. de Séréville, R. Smith, M. Stanoiu, I. Stefan, C. Stodel, D. Suzuki, J.C. Thomas, N. Timofeyuk, M. Vandebrouck, J. Walshe, and C. Wheldon
Subjects: One neutron pick-up reaction, Neutron-rich carbon isotopes, Phenomenological shell-model, Ab initio calculations, Physics, QC1-999
Abstract: The low-lying structure of 15C has been investigated via the neutron-removal 16C(d,t) reaction. Along with the known bound neutron sd-shell states, unbound p-shell hole states have been observed. The excitation energies and the deduced spectroscopic factors of the cross-shell states are an important measure of the [(p)−1(sd)2] neutron configurations in 15C. Our results show a very good agreement with shell-model calculations using the SFO-tls interaction for 15C. However, this same interaction predicted energies that were too low for the corresponding hole states in the N=9 isotone 17O and adjustment of the p-sd and sd-sd monopole terms was required to match the 17O energies. In addition, the excitation energies and spectroscopic factors have been compared to the first calculations of 15C with the ab initio self-consistent Green's function method employing the NNLOsat interaction. The results show the sensitivity to the size of the N=8 shell gap and highlight the need to go beyond the current truncation scheme.
Published: 2023
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2. Experimental investigation of ground-state properties of 7H with transfer reactions

Author: M. Caamaño, T. Roger, A.M. Moro, G.F. Grinyer, J. Pancin, S. Bagchi, S. Sambi, J. Gibelin, B. Fernández–Domínguez, N. Itagaki, J. Benlliure, D. Cortina–Gil, F. Farget, B. Jacquot, D. Pérez–Loureiro, B. Pietras, R. Raabe, D. Ramos, C. Rodríguez Tajes, H. Savajols, and M. Vandebrouck
Subjects: 7H, Hydrogen resonance, Active target, Physics, QC1-999
Abstract: The properties of nuclei with extreme neutron–to–proton ratios, far from those naturally occurring on Earth, are key to understand nuclear forces and how nucleons hold together to form nuclei. 7H, with six neutrons and a single proton, is the nuclear system with the most unbalanced neutron–to–proton ratio known so far. However, its sheer existence and properties are still a challenge for experimental efforts and theoretical models. Here we report experimental evidences on the formation of 7H as a resonance, detected with independent observables, and the first measurement of the structure of its ground state. The resonance is found at ∼0.7 MeV above the 3H+4n mass, with a narrow width of ∼0.2 MeV and a 1/2+ spin and parity. These data are consistent with a 7H as a 3H core surrounded by an extended four-neutron halo, with a unique four-neutron decay and a relatively long half-life thanks to neutron pairing; a prime example of new phenomena occurring in what would be the most pure-neutron nuclear matter we can access in the laboratory.
Published: 2022
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3. Low-lying single-particle structure of 17C and the N = 14 sub-shell closure

Author: X. Pereira-López, B. Fernández-Domínguez, F. Delaunay, N.L. Achouri, N.A. Orr, W.N. Catford, M. Assié, S. Bailey, B. Bastin, Y. Blumenfeld, R. Borcea, M. Caamaño, L. Caceres, E. Clément, A. Corsi, N. Curtis, Q. Deshayes, F. Farget, M. Fisichella, G. de France, S. Franchoo, M. Freer, J. Gibelin, A. Gillibert, G.F. Grinyer, F. Hammache, O. Kamalou, A. Knapton, T. Kokalova, V. Lapoux, J.A. Lay, B. Le Crom, S. Leblond, J. Lois-Fuentes, F.M. Marqués, A. Matta, P. Morfouace, A.M. Moro, T. Otsuka, J. Pancin, L. Perrot, J. Piot, E. Pollacco, D. Ramos, C. Rodríguez-Tajes, T. Roger, F. Rotaru, M. Sénoville, N. de Séréville, R. Smith, O. Sorlin, M. Stanoiu, I. Stefan, C. Stodel, D. Suzuki, T. Suzuki, J.C. Thomas, N. Timofeyuk, M. Vandebrouck, J. Walshe, and C. Wheldon
Subjects: Physics, QC1-999
Abstract: The first investigation of the single-particle structure of the bound states of 17C, via the d(16C,p) transfer reaction, has been undertaken. The measured angular distributions confirm the spin-parity assignments of 1/2+ and 5/2+ for the excited states located at 217 and 335 keV, respectively. The spectroscopic factors deduced for these states exhibit a marked single-particle character, in agreement with shell model and particle-core model calculations, and combined with their near degeneracy in energy provide clear evidence for the absence of the N=14 sub-shell closure. The very small spectroscopic factor found for the 3/2+ ground state is consistent with theoretical predictions and indicates that the ν1d3/2 strength is carried by unbound states. With a dominant ℓ=0 valence neutron configuration and a very low separation energy, the 1/2+ excited state is a one-neutron halo candidate.
Published: 2020
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4. Evolution of triaxial shapes at large isospin: Rh isotopes

Author: A. Navin, M. Rejmund, S. Bhattacharyya, R. Palit, G.H. Bhat, J.A. Sheikh, A. Lemasson, S. Bhattacharya, M. Caamaño, E. Clément, O. Delaune, F. Farget, G. de France, and B. Jacquot
Subjects: Isotopic identification of fission fragments, Neutron-rich Rh isotopes, Triaxial projected shell model, Nuclear triaxiality, Physics, QC1-999
Abstract: The rotational response as a function of neutron–proton asymmetry for the very neutron-rich isotopes of Rh (116–119Rh) has been obtained from the measurement of prompt γ rays from isotopically identified fragments, produced in fission reactions at energies around the Coulomb barrier. The measured energy “signature” splitting of the yrast bands, when compared with the Triaxial Projected Shell Model (TPSM) calculations, shows the need for large, nearly constant, triaxial deformations. The present results are compared with global predictions for the existence of non axial shapes in the periodic table in the case of very neutron-rich nuclei Rh isotopes. The predicted trend of a second local maximum for a triaxial shape around N∼74 is not found.
Published: 2017
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5. Electromagnetic properties of neutron-rich nuclei adjacent to the Z=50 shell closure

Author: M. Rejmund, A. Navin, S. Biswas, A. Lemasson, M. Caamaño, E. Clément, O. Delaune, F. Farget, G. de France, B. Jacquot, and P. Van Isacker
Subjects: Isotopic identification, Large isospin and high angular momentum, Spin orbit partners, In-Sb isotopes, M1/E2 transitions, Seniority, Physics, QC1-999
Abstract: Low-lying high-spin yrast states in the exotic odd–odd isotopes 124–128Sb (Z=51) and 118–128In (Z=49), studied for the first time, show a striking difference in their observed γ-ray decay. With a single valence proton particle/hole occupying the g7/2/g9/2 spin-orbit partners, dominant electric quadrupole transitions occur in Sb as opposed to magnetic dipole transitions in In. The observed properties are explained on the basis of general principles of symmetry and with large-scale shell-model calculations, and reveal novel aspects of the competition between the neutron–proton interaction and the like-nucleon pairing interaction.
Published: 2016
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6. Experimental evidence of the effect of nuclear shells on fission dissipation and time

Author: D. Ramos, M. Caamaño, F. Farget, C. Rodríguez-Tajes, A. Lemasson, C. Schmitt, L. Audouin, J. Benlliure, E. Casarejos, E. Clement, D. Cortina, O. Delaune, X. Derkx, A. Dijon, D. Doré, B. Fernández-Domínguez, G. de France, A. Heinz, B. Jacquot, C. Paradela, M. Rejmund, T. Roger, M.-D. Salsac, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay
Subjects: Nuclear Theory (nucl-th), [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: International audience; Nuclear fission is still one of the most complex physical processes we can observe in nature due to the interplay of macroscopic and microscopic nuclear properties that decide the result. An example of this coupling is the presence of nuclear dissipation as an important ingredient that contributes to drive the dynamics and has a clear impact on the time of the process. However, different theoretical interpretations, and scarce experimental data make it poorly understood. In this Letter, we present the first experimental determination of the dissipation energy in fission as a function of the fragment split, for three different fissioning systems. The amount of dissipation was obtained through the measurement of the relative production of fragments with even and odd atomic numbers with respect to different initial fission energies. The results reveal a clear effect of particular nuclear shells on the dissipation and fission dynamics. In addition, the relative production of fragments with even and odd atomic numbers appears as a potential contributor to the long-standing problem of the time scale in fission.
Published: 2023
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7. Influence of proton and neutron deformed shells on the asymmetric fission of thorium isotopes

Author: A. Chatillon, J. Taïeb, A. Heinz, H. Alvarez-Pol, L. Audouin, Y. Ayyad, G. Bélier, J. Benlliure, G. Boutoux, M. Caamaño, E. Casarejos, D. Cortina-Gil, A. Ebran, F. Farget, B. Fernández-Domínguez, T. Gorbinet, L. Grente, H. T. Johansson, B. Jurado, A. Kelić-Heil, N. Kurz, B. Laurent, J.-F. Martin, C. Nociforo, C. Paradela, E. Pellereau, S. Pietri, A. Prochazka, J. L. Rodríguez-Sánchez, D. Rossi, H. Simon, L. Tassan-Got, J. Vargas, B. Voss, H. Weick, Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Deux Infinis Bordeaux (LP2I - Bordeaux), and Université de Bordeaux (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Abstract: International audience; Mean values of the number of protons and neutrons of the primary fission fragments at scission are determined for the asymmetric fission of 16 fissioning isotopes, from Ac219 up to Np238. Our results confirm that the main asymmetric fission mode around the heavier uranium isotopes is indeed characterized by an average atomic number around 〈ZH〉=54 in the heavy fission fragments. However, they also unambiguously show a stabilization effect in the light fission fragments around 〈NL〉=52–54 in the neutron-deficient thorium and actinium isotopes. This is a clear signature that these deformed proton and neutron shell closures around 54 play a major role in the nuclear fission process. The evolution along the thorium chain shows that the neutron shell appears to be dominant in the asymmetric fission of the lighter thorium isotopes, in contrast to the heavier thorium isotopes for which the stabilization originates from the proton shell.
Published: 2022
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8. Experimental study of high-energy fission and quasi-fission dynamics with fusion-induced fission reactions at VAMOS++

Author: D. Fernández, M. Caamaño, D. Ramos, A. Lemasson, M. Rejmund, H. Álvarez-Pol, L. Audouin, J. D. Frankland, B. Fernández-Domínguez, E. Galiana-Baldó, J. Piot, C. Schmitt, D. Ackermann, S. Biswas, E. Clement, D. Durand, F. Farget, M. O. Fregeau, D. Galaviz, A. Heinz, A. Henriques, B. Jacquot, B. Jurado, Y. H. Kim, P. Morfouace, D. Ralet, T. Roger, P. Teubig, and I. Tsekhanovich
Subjects: General Medicine
Abstract: During the last decade, the use of inverse kinematics in the experimental study of fission is bringing a wealth of new observables obtained in single measurements, allowing their analysis and their correlations. An ongoing application of this technique is the basis of a series of experiments performed with the variable-mode, large-acceptance VAMOS++ spectrometer at GANIL. A recent experiment has been focused on the survival of the nuclear structure effects at high excitation energy in fission and quasi-fission. The full isotopic identification of fragments, the fission dynamics and the ratio between the production of fragments with even and odd atomic numbers, the so-called proton even-odd effect, are shown. The latter shows a different mechanism for fission and quasi-fission that could be used to separate fission from quasi-fission.
Published: 2023
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9. Fission-fragment yields measured in Coulomb-induced fission of 234,235,236,238U and 237,238Np with the R3B/SOFIA setup

Author: A. Chatillon, G. Boutoux, T. Gorbinet, L. Grente, J.-F. Martin, E. Pellereau, J. Taieb, H. Alvarez-Pol, L. Audouin, Y. Ayyad, G. Bélier, J. Benlliure, M. Caamaño, E. Casarejos, D. Cortina-Gil, A. Ebran, F. Farget, B. Fernández-Domínguez, A. Heinz, H. T. Johansson, B. Jurado, A. Kelić-Heil, N. Kurz, B. Laurent, B. Loeher, C. Nociforo, C. Paradela, S. Pietri, A. Prochazka, D. Ramos, J. L. Rodríguez-Sànchez, C. Rodriguez, D. Rossi, H. Simon, L. Tassan-Got, H. Toernqvist, J. Vargas, B. Voss, and H. Weick
Subjects: General Medicine
Abstract: Low energy fission of 234,235,236,238U and 237,238Np radioactive beams, provided by the GSI/FRS facility, has been studied using the R3B/SOFIA setup. The latter allows, on an event-by-event basis, to simultaneously identify, in terms of their mass and atomic numbers, the fissioning nucleus in coincidence with both fission fragments after prompt-neutron emission. This presentation reports on new results on elemental, isobaric and isotopic yields.
Published: 2023
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10. Ground-state properties of super-heavy hydrogen-7

Author: Marine Vandebrouck, Riccardo Raabe, A. M. Moro, Gwen Grinyer, D. Cortina, David Pérez-Loureiro, Bertrand Jacquot, M. Caamaño, Herve Savajols, S. Sambi, C. Rodriguez-Tajes, Julien Gibelin, T. Roger, D. Ramos, J. Benlliure, J. Pancin, S. Bagchi, Naoyu Itagaki, F. Farget, B. Fernández-Domínguez, Benjamim Pietras, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique Nucléaire d'Orsay (IPNO), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
Subjects: Physics, Proton, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear matter, 7. Clean energy, Resonance (particle physics), Nuclear physics, Deuterium, Nuclear force, Neutron, Nucleon, Ground state, Nuclear Experiment
Abstract: The properties of nuclei with extreme neutron-to-proton ratios, far from those naturally occurring on Earth, are key to understand nuclear forces and how nucleons hold together to form nuclei. $^7$H, with six neutrons and a single proton, is the nuclear system with the most unbalanced neutron-to-proton ratio known so far. However, its sheer existence and properties are still a challenge for experimental efforts and theoretical models. Here we report the formation of $^7$H as a resonance, detected with independent observables, and the first measurement of the structure of its ground state. The resonance is found at $\sim$0.7 MeV above the $^3$H+4n mass, with a narrow width of $\sim$0.2 MeV and a $1/2^+$ spin and parity. Together, these properties picture $^7$H as a $^3$H core surrounded by an extended four-neutron halo, with a unique four-neutron decay and a relatively long half-life thanks to neutron pairing; a prime example of new phenomena occurring in the most pure-neutron nuclear matter we can access in the laboratory.
Published: 2021

11. Fission-fragment yields and prompt-neutron multiplicity for Coulomb-induced fission of U234,235 and Np237,238

Author: S. Pietri, J. Benlliure, A. Chatillon, G. Boutoux, A. Kelic-Heil, D. M. Rossi, B. Jurado, F. Farget, A. Prochazka, C. Nociforo, J. F. Martin, E. Casarejos, Bernd Voss, B. Laurent, H. Alvarez-Pol, M. Caamaño, T. Gorbinet, Y. Ayyad, G. Belier, L. Grente, J. Vargas, D. Cortina-Gil, E. Pellereau, C. Paradela, A. Ebran, B. Fernández-Domínguez, L. Tassan-Got, Helmut Weick, L. Audouin, Andreas Martin Heinz, Håkan Johansson, N. Kurz, J. L. Rodriguez-Sanchez, J. Taieb, and Herbert A. Simon
Subjects: Physics, Proton, 010308 nuclear & particles physics, Fission, Nuclear Theory, 01 natural sciences, Nuclear physics, medicine.anatomical_structure, Prompt neutron, 0103 physical sciences, medicine, Neutron, Atomic number, Multiplicity (chemistry), Nuclear Experiment, 010306 general physics, Nucleus, Excitation
Abstract: Low-energy fission of and radioactive beams, provided by the Fragment Separator (FRS) of the GSI Helmholtzzentrum fur Schwerionenforschung facility (GSI), has been studied using the Reactions with Relativistic Radioactive Beams / Studies on Fission with Aladin (R3B/SOFIA) setup. The latter allows us, on an event-by-event basis, to simultaneously identify, in terms of their mass and atomic numbers, the fissioning nucleus in coincidence with both fission fragments after prompt-neutron emission. This article reports new results on elemental, isotonic, isobaric, and isotopic yields. Moreover, the high accuracy of our data allowed us to study in detail proton even-odd staggering, from elemental yields; neutron excess, from isotopic yields; and total prompt-neutron multiplicity, from the difference of masses of the fissioning nucleus and fission fragments. These results are then compared to previous experimental data in order to probe how these fission observables change as function of the excitation energy and atomic and neutron numbers of the compound nucleus.
Published: 2021
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12. Pseudospin-doublet bands and Gallagher Moszkowski doublet bands in Y100

Author: M. Rejmund, A. V. Ramayya, Sumita Bhattacharyya, Eric Clément, Bertrand Jacquot, S. J. Zhu, J. M. Eldridge, C. J. Zachary, F. Farget, J. H. Hamilton, N. T. Brewer, A. Lemasson, G. M. Ter-Akopian, Shishu Zhang, J. K. Hwang, Yu. Ts. Oganessian, Y. X. Luo, M. Caamaño, Qingde Chen, O. Delaune, J. O. Rasmussen, E. H. Wang, and A. Navin
Subjects: Physics, 010308 nuclear & particles physics, 01 natural sciences, Coincidence, 0103 physical sciences, Covariant transformation, Neutron, Gammasphere, Detector array, Atomic physics, 010306 general physics, Electronic band structure, Spin (physics), Spontaneous fission
Abstract: New transitions in neutron-rich Y100 have been identified in a Be9+U238 experiment with mass and Z gates to provide full fragment identification. These transitions and high spin levels of Y100 have been investigated by analyzing the high statistics γ-γ-γ and γ-γ-γ-γ coincidence data from the spontaneous fission of Cf252 at the Gammasphere detector array. Two new bands, 14 new levels, and 23 new transitions have been identified. The Kπ=4+ new band decaying to a 1s isomeric state is assigned to be the high-K Gallagher-Moszkowski (GM) partner of the known Kπ=1+ band, with the π5/2[522] - ν3/2[411] configuration. This 4+ band is also proposed to be the pseudospin partner of the new Kπ=5+ band with a 5+π5/2[422] - ν5/2[413] configuration, to form a π5/2[422] - ν[3125/2,3/2] neutron pseudospin doublet. Constrained triaxial covariant density-functional theory and quantal particle rotor model calculations have been applied to interpret the band structure and available electromagnetic transition probabilities and are found to be in good agreement with experimental values.
Published: 2021
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13. Pseudo spin doublet bands and Gallagher Moszkowski doublet bands in $^{100}$Y

Author: E. H. Wang, J. H. Hamilton, A. V. Ramayya, C. J. Zachary, A. Lemasson, A. Navin, M. Rejmund, S. Bhattacharyya, Q. B. Chen, S. Q. Zhang, J. M. Eldridge, J. K. Hwang, N. T. Brewer, Y. X. Luo, J. O. Rasmussen, S. J. Zhu, G. M. Ter-Akopian, Yu. Ts. Oganessian, M. Caamaño, E. Clément, O. Delaune, F. Farget, G. de France, B. Jacquot, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Spin states, Spectrometer, Nuclear Theory, Pseudo Spin, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Fission, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Structure, Coincidence, Nuclear Theory (nucl-th), 100Y, Gammasphere, Covariant transformation, Atomic physics, Nuclear Experiment (nucl-ex), Electronic band structure, Nuclear Experiment, GM Partner, Spontaneous fission
Abstract: New transitions in neutron rich $^{100}$Y have been identified in a $^9$Be+$^{238}$U experiment with mass- and Z- gates to provide full fragment identification. These transitions and high spin levels of $^{100}$Y have been investigated by analyzing the high statistics $\gamma$-$\gamma$-$\gamma$ and $\gamma$-$\gamma$-$\gamma$-$\gamma$ coincidence data from the spontaneous fission of $^{252}$Cf at the Gammasphere detector array. Two new bands, 14 new levels and 23 new transitions have been identified. The $K^{\pi}=4^+$ new band decaying to an 1s isomeric state is assigned to be the high-$K$ Gallagher-Moszkowski (GM) partner of the known $K^{\pi}=1^+$ band, with the $\pi 5/2[522] \otimes \nu 3/2[411]$ configuration. This 4$^+$ band is also proposed to be the pseudo spin partner of the new $K^{\pi}=5^+$ band with a 5$^{+}$ $\pi 5/2[422] \otimes \nu 5/2[413]$ configuration, to form a $\pi 5/2[422] \otimes \nu [312$ $5/2,3/2]$ neutron pseudospin doublet. Constrained triaxial covariant density functional theory and quantal particle rotor model calculations have been applied to interpret the band structure and available electromagnetic transition probabilities and are found in good agreement with experimental values.
Published: 2021
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14. Energy balance and deformation at scission in 240Pu fission

Author: M. Caamaño, F. Farget, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universidade de Santiago de Compostela. Departamento de Física de Partículas, and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Physics, Nuclear and High Energy Physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, Fission, Nuclear Theory, Evaporation, Energy balance, Deformation (meteorology), Kinetic energy, 01 natural sciences, lcsh:QC1-999, 240Pu fission, Inverse kinematics, 0103 physical sciences, Quadrupole, Fragment deformation, Atomic number, Atomic physics, 010306 general physics, Nuclear Experiment, Excitation, lcsh:Physics, Scission point
Abstract: The experimental determination of the total excitation energy, the total kinetic energy, and the evaporation neutron multiplicity of fully identified fragments produced in transfer-induced fission of 240Pu, combined with reasonable assumptions, permits to extract the intrinsic and collective excitation energy of the fragments as a function of their atomic number, along with their quadrupole deformation and their distance at scission. The results show that the deformation increases with the atomic number,Z, except for a local maximum around Z=44and a minimum around Z=50, associated with the effect of deformed shells at Z∼44, N∼64, and spherical shells in 132Sn, respectively. The distance between the fragments also shows a minimum around Z1=44, Z2=50, suggesting a mechanism that links the effect of structure with the length of the neck at scission M.C. acknowledges the financial support of the Program“Ramón y Cajal” of the Ministerio de Economía y Competitividad of Spain through the grant number RYC-2012-11585 SI
Published: 2017
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15. Scission configuration of U239 from yields and kinetic information of fission fragments

Author: T. Roger, D. Ramos, M.O. Frégeau, I. Tsekhanovich, E. Galiana-Baldó, A. Henriques, P. Morfouace, B. Jacquot, C. Schmitt, M. Caamaño, S. Biswas, M. Rejmund, J. Piot, B. Jurado, Andreas Martin Heinz, B. Fernández-Domínguez, L. Audouin, Y.H. Kim, F. Farget, P. Teubig, A. Lemasson, D. Durand, D. Ralet, Dieter Ackermann, H. Alvarez-Pol, Emyr Clement, Daniel Galaviz, and J.D. Frankland
Subjects: Nuclear reaction, Physics, Proton, 010308 nuclear & particles physics, Fission, Nuclear Theory, Kinetic energy, 01 natural sciences, 7. Clean energy, Nuclear physics, 0103 physical sciences, Neutron, Nuclear Experiment, 010306 general physics, Nucleon, Excitation, Beam (structure)
Abstract: The simultaneous measurement of the isotopic fission-fragment yields and fission-fragment velocities of U239 has been performed for the first time. The U239 fissioning system was produced in one-neutron transfer reactions between a U238 beam at 5.88 MeV/nucleon and a Be9 target. The combination of inverse kinematics at low energy and the use of the VAMOS++ spectrometer at the GANIL facility allows the isotopic identification of the full fission-fragment distribution and their velocity in the reference frame of the fissioning system. The proton and neutron content of the fragments at scission, their total kinetic and total excitation energy, as well as the neutron multiplicity were determined. Information from the scission point configuration is obtained from these observables and the correlation between them. The role of the octupole-deformed proton and neutron shells in the fission-fragment production is discussed.
Published: 2020
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16. Evidence for a New Compact Symmetric Fission Mode in Light Thorium Isotopes

Author: Andreas Martin Heinz, M. Caamaño, Enrique Casarejos, A. Ebran, Yassid Ayyad, A. Chatillon, G. Boutoux, J. Taieb, J. Vargas, J. L. Rodriguez-Sanchez, T. Gorbinet, B. Laurent, F. Farget, A. Prochazka, S. Pietri, D. Cortina-Gil, C. Nociforo, C. Paradela, B. Fernández-Domínguez, E. Pellereau, L. Audouin, N. Kurz, Helmut Weick, Håkan T Johansson, L. Grente, Herbert A. Simon, J. Benlliure, H. Alvarez-Pol, D. M. Rossi, Bernd Voss, G. Belier, J. F. Martin, L. Tassan-Got, A. Kelic-Heil, Beatriz Jurado, Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Isotope, Fission, Nuclear Theory, General Physics and Astronomy, Thorium, chemistry.chemical_element, Actinide, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Effective nuclear charge, Physics::Geophysics, Nuclear physics, chemistry, 0103 physical sciences, Multiplicity (chemistry), 010306 general physics, Nuclear Experiment, Bond cleavage, Isotopes of thorium, Nuclear Physics
Abstract: International audience; Taking benefit of the R3B/SOFIA setup to measure the mass and the nuclear charge of both fission fragments in coincidence with the total prompt-neutron multiplicity, the scission configurations are inferred along the thorium chain, from the asymmetric fission in the heavier isotopes to the symmetric fission in the neutron-deficient thorium. Against all expectations, the symmetric scission in the light thorium isotopes shows a compact configuration, which is in total contrast to what is known in the fission of the heavier thorium isotopes and heavier actinides. This new main symmetric scission mode is characterized by a significant drop in deformation energy of the fission fragments of about 19 MeV, compared to the well-known symmetric scission in the uranium-plutonium region.
Published: 2020
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17. Structure of superheavy hydrogen 7H

Author: Naoyuki Itagaki, A. M. Moro, J. Gibelin, D. Cortina-Gil, C. Rodríguez Tajes, B. Fernández–Domínguez, G. F. Grinyer, F. Farget, D. Perez Loureiro, Riccardo Raabe, J. Pancin, J. Benlliure, S. Sambi, S. Bagchi, M. Caamaño, Bertrand Jacquot, T. Roger, Marine Vandebrouck, H. Savajols, B. Pietras, D. Ramos, Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Universidade de Santiago de Compostela [Spain] (USC ), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universidad de Sevilla / University of Sevilla, KVI-CART, University of Groningen, University of Groningen [Groningen], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Yukawa Institute for Theoretical Physics (YITP), Kyoto University, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, [PHYS]Physics [physics], Proton, Hydrogen, 010308 nuclear & particles physics, QC1-999, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, chemistry.chemical_element, Nuclear matter, 01 natural sciences, 7. Clean energy, Nuclear physics, chemistry, Pairing, 0103 physical sciences, Nuclear force, Neutron, Halo, 010306 general physics, Ground state, Nuclear Experiment
Abstract: The properties of nuclei with extreme neutron–to–proton ratios reveal the limitations of state-ofthe-art nuclear models and are key to understand nuclear forces. 7H, with six neutrons and a single proton, is the nuclear system with the most unbalanced neutron–to–proton ratio ever known, but its sheer existence and properties are still a challenge for experimental efforts and theoretical models. We report here the first measurement of the basic characteristics and structure of the ground state of 7H; they depict a system with a triton core surrounded by an extended four-neutron halo, built by neutron pairing, that decays through a unique four–neutron emission with a relatively long half-life. These properties are a prime example of new phenomena occurring in almost pure-neutron nuclear matter, beyond the binding limits of the nuclear landscape, that are yet to be described within our current models.
Published: 2020
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18. Experimental study of nuclear fission along the thorium isotopic chain: From asymmetric to symmetric fission

Author: Helmut Weick, Laurent Tassan-Got, Håkan T Johansson, T. Gorbinet, L. Grente, J. Vargas, Herbert A. Simon, M. Caamaño, A. Kelic-Heil, S. Pietri, E. Casarejos, B. Laurent, Andreas Martin Heinz, J-F Martin, E. Pellereau, F. Farget, H. Alvarez-Pol, N. Kurz, L. Audouin, B. Jurado, J. Benlliure, Bernd Voss, A. Ebran, A. Prochazka, C. Paradela, J. Taieb, J. L. Rodriguez-Sanchez, Yassid Ayyad, G. Belier, B. Fernández-Domínguez, D. Cortina-Gil, C. Nociforo, A. Chatillon, G. Boutoux, Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear reaction, Physics, 010308 nuclear & particles physics, Fission, Nuclear Theory, Thorium, chemistry.chemical_element, Coulomb excitation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, chemistry, Nuclear fission, 0103 physical sciences, Nuclear Reactions, Physics::Atomic and Molecular Clusters, Isobaric process, ddc:530, Atomic number, Nuclear Experiment, 010306 general physics, Excitation
Abstract: International audience; The inverse kinematics technique, applied to radioactive beams and combined to the Coulomb excitation method, is a powerful tool to study low-energy fission. A novel experimental setup was developed within the R3B/SOFIA (Reactions with Relativistic Radioactive Beams/Studies On FIssion with Aladin) collaboration to identify in mass and atomic numbers both fission fragments in coincidence. These new data provide elemental, isobaric, and isotonic yields for the fission along the thorium isotopic chain. Results are also compared to previous measurements using either the same reaction mechanism or thermal-neutron induced fission. This latter comparison permits to probe the influence of the excitation energy in the fission process.
Published: 2019
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19. Study of High-Energy Fission in Inverse Kinematics

Author: G. Mantovani, L. Audoin, Y. H. Kim, F. Gramegna, H. Alvarez Pol, J.D. Frankland, Bertrand Jacquot, M. Rejmund, M.O. Frégeau, B. Jurado, D. Ramos, I. Tsekhanovich, J. Piot, Andreas Martin Heinz, F. Farget, T. Marchi, S. Biswas, D. Galaviz, C. Schmitt, M. Caamaño, A. Henriques, Dieter Ackermann, E. Galiana-Baldo, D. Ralet, Dominique Durand, Eric Clément, P. Morfouace, Magda Cicerchia, T. Roger, B. Fernández-Domínguez, A. Lemasson, P. Teubig, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Inverse kinematics, Series (mathematics), 010308 nuclear & particles physics, Fission, QC1-999, Nuclear Theory, Shell (structure), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Kinetic energy, 01 natural sciences, Nuclear physics, 0103 physical sciences, Physics::Atomic and Molecular Clusters, 010306 general physics, Nuclear Experiment, Energy (signal processing), Excitation, Beam (structure)
Abstract: Fission at low excitation energy, is a process in which both macroscopic and microscopic aspects are involved. Some features in the total kinetic energy and in the N/Z distributions of the fragments, commonly associated with shell effects, came out in a series of recent experiments with high excitation energy fusionfission reactions in inverse kinematics. In the latest experiment of this campaign, a study of high-energy fission and quasi-fission between a 238U beam and a series of light targets was carried out by using the aforementioned technique, in order to probe the role of the shell structure in these processes.
Published: 2019
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20. First inverse-kinematics fission measurements in a gaseous active target

Author: P. Konczykowski, C. Rodriguez-Tajes, M. Caamaño, G. Randisi, J. Pancin, F. Boulay, F. Farget, T. Roger, D. Galaviz, Mathieu Babo, B. Fernández-Domínguez, Ismael Martel, A. M. Sánchez-Benítez, Mohsen Harakeh, S. Damoy, L. Acosta, H. Alvarez-Pol, Marine Vandebrouck, P. Teubig, J. Grinyer, Francesca Renzi, G. F. Grinyer, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), KVI-CART, University of Groningen, University of Groningen [Groningen], Research unit Nuclear & Hadron Physics, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear reaction, Nuclear and High Energy Physics, Fission, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Kinetic energy, 01 natural sciences, Nuclear physics, ENERGY, MAYA, Nucleosynthesis, 0103 physical sciences, 010306 general physics, Nuclear Experiment, Fusion, DETECTOR, Physics, MULTINUCLEON TRANSFER, Inverse kinematics, 010308 nuclear & particles physics, BEAMS, BARRIER, Nucleon transfer, Uranium-238, Surrogate reactions, ACTINIDES, Active target, Excitation, Beam (structure), SYSTEM
Abstract: The fission of a variety of actinides was induced by fusion and transfer reactions between a U-238 beam and C-12 nuclei, in the active target MAYA. The performance of MAYA was studied, as well as its capability to reconstruct the fission-fragment trajectories. Furthermore, a full characterization of the different transfer reactions was achieved, and the populated excitation-energy distributions were investigated as a function of the kinetic energy in the entrance channel. The ratio between transfer- and fusion-induced fission cross sections was also determined, in order to investigate the competition between both reaction types and its evolution with the incident energy. The experimental results will be discussed with a view to forthcoming radioactive-ion beam facilities, and next-generation active-target setups. (C) 2016 Elsevier B.V. All rights reserved.
Published: 2017
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21. Insight into excitation energy and structure effects in fission from isotopic information in fission yields

Author: D. Ramos, M. Caamaño, F. Farget, C. Rodríguez-Tajes, L. Audouin, J. Benlliure, E. Casarejos, E. Clement, D. Cortina, O. Delaune, X. Derkx, A. Dijon, D. Doré, B. Fernández-Domínguez, G. de France, A. Heinz, B. Jacquot, C. Paradela, M. Rejmund, T. Roger, M.-D. Salsac, C. Schmitt, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut Pluridisciplinaire Hubert Curien (IPHC), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, [PHYS]Physics [physics], Spectrometer, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, Fission, Nuclear Theory, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, 0103 physical sciences, Nuclear fusion, Neutron, Atomic number, Multiplicity (chemistry), 010306 general physics, Nuclear Experiment, Excitation, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; The use of the inverse kinematics technique and a magnetic spectrometer permits the simultaneous measurement of proton and neutron content of full fission fragment distributions. This paper reports new measurements of five fissioning systems—U238,Np239,Pu240,Cm244, and Cf250—produced in inelastic scattering, transfer, and fusion reactions at different excitation energies. As a result, isotopic, elemental, and isotonic fission yields are presented. The contribution of the different fission modes and the proton even-odd effect are studied. Structure effects are investigated by means of the neutron excess and the total neutron multiplicity as a function of the fragment atomic number.
Published: 2019
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22. First Direct Measurement of Isotopic Fission-Fragment Yields of U 239

Author: D. Ramos, M. Caamaño, A. Lemasson, M. Rejmund, L. Audouin, H. Álvarez-Pol, J. D. Frankland, B. Fernández-Domínguez, E. Galiana-Baldó, J. Piot, D. Ackermann, S. Biswas, E. Clement, D. Durand, F. Farget, M. O. Fregeau, D. Galaviz, A. Heinz, A. I. Henriques, B. Jacquot, B. Jurado, Y. H. Kim, P. Morfouace, D. Ralet, T. Roger, C. Schmitt, P. Teubig, I. Tsekhanovich
Published: 2019
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23. First Direct Measurement of Isotopic Fission-Fragment Yields of $^{239}$U

Author: D, Ramos, M, Caamaño, A, Lemasson, M, Rejmund, L, Audouin, H, Álvarez-Pol, J D, Frankland, B, Fernández-Domínguez, E, Galiana-Baldó, J, Piot, D, Ackermann, S, Biswas, E, Clement, D, Durand, F, Farget, M O, Fregeau, D, Galaviz, A, Heinz, A I, Henriques, B, Jacquot, B, Jurado, Y H, Kim, P, Morfouace, D, Ralet, T, Roger, C, Schmitt, P, Teubig, I, Tsekhanovich, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment, Nuclear Physics
Abstract: International audience; A direct and complete measurement of isotopic fission-fragment yields of U239 has been performed for the first time. The U239 fissioning system was produced with an average excitation energy of 8.3 MeV in one-neutron transfer reactions between a U238 beam and a Be9 target at Coulomb barrier energies. The fission fragments were detected and isotopically identified using the VAMOS++ spectrometer at the GANIL facility. The measurement allows us to directly evaluate the fission models at excitation energies of fast neutrons, which are relevant for next-generation nuclear reactors. The present data, in agreement with model calculations, do not support the recently reported anomaly in the fission-fragment yields of U239, and they confirm the persistence of spherical shell effects in the Sn region at excitation energies exceeding the fission barrier by a few mega-electron volts.
Published: 2019
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24. Evidence for Coexisting Shapes through Lifetime Measurements in Zr98

Author: M. D. Salsac, W. Rother, F. Recchia, Alfred Dewald, Nathalie Pillet, Andreas Görgen, Jean Paul Delaroche, C. Michelagnoli, M. Hackstein, C. Louchart, C. Müller-Gatermann, B. Bruyneel, W. Korten, J. Libert, Igor T. Čeliković, A. Dijon, Trine Wiborg Hagen, Bertrand Jacquot, J. Ljungvall, Emmanuel Clément, F. Farget, Takaharu Otsuka, C Theisen, D. R. Napoli, B. Sulignano, J. Litzinger, Purnima Singh, Jose Javier Valiente-Dobón, E. Sahin, Tomoaki Togashi, L. Grente, Yuhsuke Tsunoda, O. Delaune, Thomas Braunroth, A. Gottardo, Sunniva Siem, and Michel Girod
Subjects: Physics, Spectrometer, 010308 nuclear & particles physics, Fission, SHELL model, General Physics and Astronomy, 01 natural sciences, Nuclear fission, Excited state, 0103 physical sciences, Atomic number, Atomic physics, Nuclear Experiment, 010306 general physics, Ground state, Beam (structure)
Abstract: The lifetimes of the first excited 2^{+}, 4^{+}, and 6^{+} states in ^{98}Zr were measured with the recoil-distance Doppler shift method in an experiment performed at GANIL. Excited states in ^{98}Zr were populated using the fission reaction between a 6.2 MeV/u ^{238}U beam and a ^{9}Be target. The γ rays were detected with the EXOGAM array in correlation with the fission fragments identified by mass and atomic number in the VAMOS++ spectrometer. Our result shows a very small B(E2;2_{1}^{+}→0_{1}^{+}) value in ^{98}Zr, thereby confirming the very sudden onset of collectivity at N=60. The experimental results are compared to large-scale Monte Carlo shell model and beyond-mean-field calculations. The present results indicate the coexistence of two additional deformed shapes in this nucleus along with the spherical ground state.
Published: 2018
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25. Deformed band structures in neutron-rich Pm152–158 isotopes

Author: M. Caamaño, Bertrand Jacquot, M. Rejmund, A. V. Afanasjev, Sumita Bhattacharyya, E. H. Wang, A. V. Ramayya, J. H. Hamilton, Soumik Bhattacharya, A. Navin, Y. X. Luo, Yu. Ts. Oganessian, F. Farget, J. O. Rasmussen, A. Lemasson, S. J. Zhu, O. Delaune, Eric Clément, J. Ranger, G. M. Ter-Akopian, and J. K. Hwang
Subjects: Physics, education.field_of_study, Spins, 010308 nuclear & particles physics, Fission, Astrophysics::High Energy Astrophysical Phenomena, Population, Parity (physics), 01 natural sciences, Excited state, 0103 physical sciences, Gammasphere, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, education, Spontaneous fission
Abstract: High spin band structures of neutron-rich $^{152--158}\mathrm{Pm}$ isotopes have been obtained from the measurement of prompt $\ensuremath{\gamma}$ rays of isotopically identified fragments produced in fission of $^{238}\mathrm{U}+^{9}\mathrm{Be}$ and detected using the VAMOS++ magnetic spectrometer and EXOGAM segmented Clover array at GANIL and also from the high statistics $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ and $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ data from the spontaneous fission of $^{252}\mathrm{Cf}$ using Gammasphere. The excited states in $^{157}\mathrm{Pm}$ and those above the isomers in even-$A$ Pm isotopes $^{152,154,156,158}\mathrm{Pm}$ have been identified for the first time. The spectroscopic information on the rotational band structures in odd-$A$ Pm isotopes has been extended considerably to higher spins and the possibility of the presence of reflection asymmetric shapes is explored. The configuration assignments are based on the results of cranked relativistic Hartree-Bogoliubov calculations. From the systematics of bands in odd-$A$ Pm isotopes and weak population of opposite parity bands, octupole deformed shapes in neutron-rich Pm isotopes beyond $N=90$ seem unlikely to be present.
Published: 2018
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26. Isotopic fission-fragment distributions of U238, Np239, Pu240, Cm244 , and Cf250 produced through inelastic scattering, transfer, and fusion reactions in inverse kinematics

Author: D. Ramos, M. Caamaño, F. Farget, C. Rodríguez-Tajes, L. Audouin, J. Benlliure, E. Casarejos, E. Clement, D. Cortina, O. Delaune, X. Derkx, A. Dijon, D. Doré, B. Fernández-Domínguez, G. de France, A. Heinz, B. Jacquot, A. Navin, C. Paradela, M. Rejmund, T. Roger, M.-D. Salsac, and C. Schmitt
Subjects: Physics, Range (particle radiation), Spectrometer, 010308 nuclear & particles physics, Fission, Nuclear Theory, Inelastic scattering, 01 natural sciences, 7. Clean energy, Effective nuclear charge, Nuclear physics, Nuclear fission, 0103 physical sciences, Nuclear fusion, Nuclear Experiment, 010306 general physics, Excitation
Abstract: Transfer- and fusion-induced fission in inverse kinematics has proved to be a powerful tool to investigate nuclear fission, widening information on the fission fragments and access to unstable fissioning systems with respect to other experimental approaches. An experimental campaign is being carried out at GANIL with this technique since 2008. In these experiments, a beam of U-238, accelerated to 6.1 MeV/u, impinges on a C-12 target. Fissioning systems from U to Cf are populated through inelastic scattering, transfer, and fusion reactions, with excitation energies that range from a few MeV up to 46 MeV. The use of inverse kinematics, the SPIDER telescope, and the VAMOS spectrometer allow the characterization of the fissioning system in terms of mass, nuclear charge, and excitation energy, and the isotopic identification of the full fragment distribution. This work reports on new data from the second experiment of the campaign on fission-fragment yields of the heavy actinides U-238, Np-239, Pu-240, Cm-244, and Cf-250, which are of interest from both fundamental and application points of view.
Published: 2018
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27. Fission fragment yields from heavy-ion-induced reactions measured with a fragment separator

Author: B. M. Sherrill, S. M. Lukyanov, A. M. Amthor, Daniel Bazin, C. Stodel, H. Savajols, B. Blank, L. Caceres, J. Pereira, B. Bastin, Wolfgang Mittig, O. Kamalou, J. C. Thomas, S. Grévy, L. Perrot, O. Delaune, F. Farget, David J. Morrissey, Antonio Villari, Oleg B. Tarasov, M. G. Saint-Laurent, A. Chbihi, B. Fernández-Domínguez, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Nuclear reaction, Nuclear and High Energy Physics, Nuclear fission product, Fission products, Isotope, 010308 nuclear & particles physics, Fission, Nuclear Theory, Fission product yield, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Nuclear physics, 0103 physical sciences, Nuclear fusion, Atomic number, 010306 general physics, Nuclear Experiment
Abstract: The systematic study of fission fragment yields under different initial conditions has provided valuable experimental data for benchmarking models of fission product yields. Nuclear reactions using inverse kinematics coupled to the use of a high-resolution spectrometer with good fragment identification are shown here to be a powerful tool to measure the inclusive isotopic yields of fission fragments. In-flight fusion-fission was used in this work to produce secondary beams of neutron-rich isotopes in the collisions of a 238U beam at 24 MeV/u with 9Be and 12C targets at GANIL using the LISE3 fragment separator. Unique identification of the A, Z, and atomic charge state, q, of fission products was attained with the $\Delta E$ -TKE-B $\rho$ -ToF measurement technique. Mass, and atomic number distributions are reported for the two reactions. The results show the importance of different reaction mechanisms in the two cases. The optimal target material for higher yields of neutron-rich high-Z isotopes produced in fusion-fission reactions as a function of projectile energy is discussed.
Published: 2018
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28. Lifetimes of excited states in triaxially deformed $^{107}$Tc and $^{109,111,113}$Rh

Author: Igor T. Čeliković, W. Rother, Jose Javier Valiente-Dobón, C. Louchart, Bertrand Jacquot, L. Grente, W. Korten, B. Sulignano, E. Sahin, C Theisen, A. Dijon, Emmanuel Clément, Andreas Görgen, Sunniva Siem, F. Recchia, C. Michelagnoli, M. D. Salsac, J. Ljungvall, O. Delaune, Thomas Braunroth, D. R. Napoli, B. Bruyneel, M. Hackstein, Trine Wiborg Hagen, F. Farget, Alfred Dewald, J. Litzinger, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Nuclear and High Energy Physics, differential plunger, Spectrometer, 010308 nuclear & particles physics, Fission, Yrast, Hadron, Nuclear Theory, 100 region, fission fragments, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], high-spin structure, 7. Clean energy, 01 natural sciences, rotational bands, Excited state, 0103 physical sciences, Nuclear fusion, Atomic number, Atomic physics, 010306 general physics, Nuclear Experiment, Beam (structure)
Abstract: Lifetimes of excited states in 107Tc, 109Rh, 111Rh, and 113Rh were measured at GANIL using the Recoil-Distance Doppler Shift method. The neutron-rich nuclei were produced in fission reactions in inverse kinematics with a 238U beam impinging on a 9Be target. Fission fragments were identified event-by-event in the ray-tracing spectrometer VAMOS++ and correlated with prompt $\gamma$ rays observed around the target position with the EXOGAM Ge detector array. Several lifetimes were obtained for states in the positive-parity yrast bands in the four nuclei and compared to triaxial particle-rotor calculations. The results clarify the configuration for the strongest positive-parity band in 107Tc and suggest a gradual increase of triaxial deformation with atomic number Z, reaching almost maximum triaxiality for the neutron-rich Rh nuclei.
Published: 2018
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29. Access to Scission Observables from Fission Fragment Velocities

Author: M. Caamaño, F. Farget, Universidade de Santiago de Compostela [Spain] (USC ), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), GANILEXP, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Fission, TKE, Fragment Velocity, Neutron evaporation, Evaporation, Observable, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Physics and Astronomy(all), Kinetic energy, Configuration at Scission, Nuclear physics, Fragment Deformation, Fragment Z, Fragment (logic), Scientific method, Fragment Mass, Momentum conservation, Nuclear Experiment, Bond cleavage
Abstract: International audience; Experimental measurements of the products of fission reactions are generally biased by evaporation stages before and after the fission process. Its complexity needs as many observables as possible to check the present models and reveal new correlations. Fully identified fission fragments and their velocities can provide new information as well as be a probe for current descriptions and models. By means of momentum conservation, the measured velocities provide information on mass, total kinetic energy, and geometrical configuration at scission.
Published: 2015
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30. Accurate isotopic fission yields of electromagnetically induced fission of U238 measured in inverse kinematics at relativistic energies

Author: Andreas Martin Heinz, K.-H. Schmidt, Helmut Weick, S. Pietri, Håkan T Johansson, J. Vargas, D. Cortina-Gil, B. Jurado, C. Paradela, B. Laurent, L. Audouin, A. Kelic-Heil, A. Ebran, G. Belier, J. L. Rodriguez-Sanchez, Y. Ayyad, J. Benlliure, A. Chatillon, F. Farget, J. Taieb, E. Pellereau, G. Boutoux, T. Gorbinet, C. Nociforo, J. F. Martin, B. Fernández-Domínguez, L. Tassan-Got, E. Casarejos, H. Alvarez-Pol, L. Grente, Herbert A. Simon, N. Kurz, Bernd Voss, and M. Caamaño
Subjects: Physics, Range (particle radiation), Inverse kinematics, 010308 nuclear & particles physics, Fission, Nuclear Theory, 01 natural sciences, 7. Clean energy, Coincidence, Effective nuclear charge, Nuclear physics, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Physics::Accelerator Physics, Nuclear Experiment, 010306 general physics
Abstract: SOFIA (Studies On Fission with Aladin) is a novel experimental program, dedicated to accurate measurements of fission-fragment isotopic yields. The setup allows us to fully identify, in nuclear charge and mass, both fission fragments in coincidence for the whole fission-fragment range. It was installed at the GSI facility (Darmstadt), to benefit from the relativistic heavy-ion beams available there, and thus to use inverse kinematics. This paper reports on fission yields obtained in electromagnetically induced fission of U238.
Published: 2017
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31. Isotopic production cross sections of residual nuclei in the spallation reactionXe136(200AMeV)+p

Author: V. Henzl, C. Stephan, A. Lafriaskh, Enrique Casarejos, A. Kelic-Heil, J.E. Ducret, K.-H. Schmidt, Andreas Martin Heinz, L. Giot, M. Fernández Ordóñez, J. Benlliure, A. Boudard, C. Volant, C. Schmitt, O. Yordanov, C. Villagrasa, B. Fernández-Domínguez, S. Leray, D. Henzlova, D. Pérez-Loureiro, M. V. Ricciardi, P. Napolitani, F. Farget, J. Pereira, T. Enqvist, L. Tassan-Got, C. Paradela, L. Audouin, and J. L. Rodriguez-Sanchez
Subjects: Physics, Spectrometer, 010308 nuclear & particles physics, Projectile, Nuclear Theory, chemistry.chemical_element, Residual, 01 natural sciences, Nuclear physics, chemistry, Cascade, Caesium, 0103 physical sciences, Physics::Accelerator Physics, Neutron source, Spallation, Atomic physics, Nuclear Experiment, 010306 general physics, Radioactive beam
Abstract: The residual nuclei produced in the spallation reaction of Xe-136 nuclei at 200A MeV on protons have been studied by measuring the isotopic distributions for the elements from cadmium (Z = 48) to cesium (Z = 55) by using the fragment separator (FRS) spectrometer at GSI and the inverse kinematics technique. This is one of the few measurements performed at such a low projectile energy, close to the validity limit for intranuclear cascade models such as INCL or ISABEL. The experimental results have been compared to these intranuclear cascade codes coupled to the evaporation code ABLA. Both code combinations reproduce qualitatively the measured isotopic distributions; however, both underestimate the production of residues with mass numbers between 126 and 134. The measured cross sections are of interest for the planning of future radioactive beam or neutron source facilities.
Published: 2017
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32. Towards the high spin–isospin frontier using isotopically-identified fission fragments

Author: A. Navin, M. Rejmund, C. Schmitt, S. Bhattacharyya, G. Lhersonneau, P. Van Isacker, M. Caamaño, E. Clément, O. Delaune, F. Farget, G. de France, B. Jacquot, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Variable Energy Cyclotron Centre, Universidade de Santiago de Compostela [Spain] (USC ), and Universidade de Santiago de Compostela. Departamento de Física de Partículas
Subjects: Interacting boson model, Physics, Nuclear and High Energy Physics, Isotope, Fission, Fission fragments, Nuclear Theory, Coulomb barrier, Interacting Boson Model, Context (language use), fission fragments, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Isotopic identification, large isospin and high angular momentum, Large isospin and high angular momentum, Neutron-rich Zr isotopes, Nuclear physics, isotopic identification, Isospin, neutron-rich Zr isotopes, Isotopes of zirconium, Atomic physics, Nuclear Experiment, Spin (physics)
Abstract: Measurements of prompt γ rays in coincidence with isotopically-identified fission fragments, produced in collisions of 238 U on a 9 Be target, at an energy around the Coulomb barrier are reported. This technique provides simultaneous access to the spectroscopy of many nuclei, extending to very neutron-rich isotopes and fairly high angular momenta. The structural evolution of the neutron-rich zirconium isotopes is discussed in the light of the present measurements in Zr105,106 and in the context of the interacting boson model with a global parameterization that includes triaxiality but no shape coexistence.
Published: 2014
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33. High-precision measurement of isotopic fission yields of $^{236}$U

Author: S. Pietri, B. Jurado, Herbert A. Simon, M. Caamaño, B. Löher, L. Grente, C. Paradela, F. Farget, A. Chatillon, L. Audouin, Simon Lindberg, G. Boutoux, B. Laurent, G. Belier, Enrique Casarejos, H. Alvarez-Pol, K.-H. Schmidt, C. Rodriguez-Tajes, N. Kurz, J. L. Rodriguez-Sanchez, J. F. Martin, D. Ramos, Andreas Martin Heinz, L. Tassan-Got, D. M. Rossi, J. Benlliure, Bernd Voss, C. Nociforo, H. Törnqvist, A. Kelic-Heil, Y. Yan, D. Cortina-Gil, Helmut Weick, Håkan T Johansson, Y. Ayyad, T. Gorbinet, B. Fernández-Domínguez, J. Taieb, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Physics, Inverse kinematics, Spectrometer, 010308 nuclear & particles physics, Fission, QC1-999, Nuclear data, Charge (physics), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Recoil, 0103 physical sciences, 010306 general physics, Spectroscopy, Nuclear Experiment, Beam (structure)
Abstract: We report on the second SOFIA experiment, dedicated to the fission yields of 236U*, analog to 235U(n,f). The measurement is based on the inverse kinematics method, using a relativistic, secondary beam of 236U. Both fission fragments are identified in mass and charge in the SOFIA recoil spectrometer. The obtained isotopic yields are compared with existing spectroscopy measurements and the elemental yields are used to discuss the treatment of the even-odd effect with energy in nuclear data libraries.
Published: 2017
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34. Time-dependent mean-field determination of the excitation energy in transfer reactions: Application to the reaction U238 on C12 at 6.14 MeV/nucleon

Author: Denis Lacroix, F. Farget, Guillaume Scamps, and C. Rodriguez-Tajes
Subjects: Physics, Imagination, Fusion, 010308 nuclear & particles physics, media_common.quotation_subject, 01 natural sciences, Nuclear physics, Mean field theory, 0103 physical sciences, Atomic physics, Microscopic theory, 010306 general physics, Nucleon, Beam (structure), Energy (signal processing), Excitation, media_common
Abstract: The internal excitation of nuclei after multinucleon transfer is estimated by using the time-dependent mean-field theory. Transfer probabilities for each channel as well as the energy loss after reseparation are calculated. By combining these two pieces of information, we show that the excitation energy distribution of the transfer fragments can be obtained separately for the different transfer channels. The method is applied to the reaction involving a $^{238}\mathrm{U}$ beam on a $^{12}\mathrm{C}$ target, which has recently been measured at GANIL. It is shown that the excitation energy calculated with the microscopic theory compares well with the experimental observation, provided that the competition with fusion is properly taken into account. The reliability of the excitation energy is further confirmed by the comparison with the phenomenological heavy-ion phase-space model at higher center-of-mass energies.
Published: 2017
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35. Fission in Inverse Kinematics: A path to new experimental observables

Author: D. Ramos, F. Farget, M. Caamaño, Universidade de Santiago de Compostela [Spain] (USC ), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), E.C. Simpson, C. Simenel, K.J. Cook and I.P. Carter, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Inverse kinematics, 010308 nuclear & particles physics, Fission, QC1-999, Inverse, Observable, Kinematics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Fragment (logic), 0103 physical sciences, Path (graph theory), Point (geometry), Statistical physics, 010306 general physics, Nuclear Experiment
Abstract: International audience; Historically, experimental fission studies were based on reactions in direct kinematics with fixed target-like fissioning systems. Besides its advantages, this technique suffers from some drawbacks such as the difficulty of producing exotic fissioning systems and the seldom measurement of the fragment atomic number. Inverse kinematic provides an alternative to ease these issues and offers a new set of experimental observables that improves our level of information about the fission process, including an unprecedented access to the scission point. In this document, we review some of the observables obtained from the experimental campaign based on inverse kinematics, performed at VAMOS/GANIL.
Published: 2017
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36. Evolution of nuclear shapes in odd-mass yttrium and niobium isotopes from lifetime measurements following fission reactions

Author: F. Farget, E. Clément, C. Louchart, Igor T. Čeliković, J. Ljungvall, Bertrand Jacquot, Ingemar Ragnarsson, O. Delaune, Thomas Braunroth, L. Grente, Andreas Görgen, Sunniva Siem, A. Dewald, M. Hackstein, B. Bruyneel, W. Rother, A. Dijon, C. Theisen, B. Sulignano, F. Recchia, E. Sahin, D. R. Napoli, M. D. Salsac, Trine Wiborg Hagen, J. J. Valiente-Dobón, C. Michelagnoli, W. Korten, J. Litzinger, Department of Physics [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), European Project: 262010,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2010-1,ENSAR(2010), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Fission, Nuclear Theory, DIFFERENTIAL PLUNGER, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ELECTRIC MONOPOLE TRANSITIONS, 7. Clean energy, 01 natural sciences, Nuclear physics, Recoil, DEFORMATION, 0103 physical sciences, TRIAXIALITY, SPECTROMETER, 010306 general physics, Nuclear Experiment, FRAGMENTS, NEUTRON-RICH NUCLEI, Physics, Isotope, HIGH-SPIN, 010308 nuclear & particles physics, ROTATIONAL BANDS, Yttrium, chemistry, GROUND-STATE, Neutron number, Excited state, Atomic number, Atomic physics, Ground state
Abstract: International audience; Lifetimes of excited states in ${}^{99}$Y , ${}^{101}$Y, ${}^{101}$Nb, ${}^{103}$Nb, and ${}^{105}$Nb were measured in an experiment using the recoil distance Doppler shift method at GANIL (Grand Accélérateur National d’Ions Lourds). The neutron-richnuclei were produced in fission reactions between a ${}^{238}$U beam and a ${}^9$Be target. Prompt γ rays were measuredwith the EXOGAM array and correlated with fission fragments that were identified in mass and atomic numberwith the VAMOS$\ {++}$ spectrometer. The measured lifetimes, together with branching ratios, provide $\it B(M1)$ and$\it B(E2)$ values for the strongly coupled rotational bands built on the [422]5/2$^+$ ground state in the Y and Nb nucleiwith neutron number N $\geq$ 60. The comparison of the experimental results with triaxial particle-rotor calculationsprovides information about the evolution of the nuclear shape in this mass region.
Published: 2017
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37. Study of fusion-fission in inverse kinematics with a fragment separator

Author: F. Farget, S. Grévy, A. Chbihi, O. Delaune, L. Perrot, B. M. Sherrill, J. C. Thomas, B. Blank, Daniel Bazin, J. Pereira, C. Stodel, Wolfgang Mittig, Antonio Villari, David J. Morrissey, A. M. Amthor, S. M. Lukyanov, O. Kamalou, B. Fernández-Domínguez, H. Savajols, B. Bastin, L. Caceres, M. G. Saint-Laurent, Oleg B. Tarasov, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Yu. E. Penionzhkevich, Yu.G. Sobolev, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Fission products, Fussion-fission, Inverse kinematics, Isotope, Spectrometer, Fragment separator, Fission, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Collision, LISE, Nuclear physics, Atomic number, GANIL EXP, Nuclear Experiment (nucl-ex), Nuclear Experiment, Beam (structure), LISE++ code, Secondary beams
Abstract: The systematic study of fission fragment yields under different initial conditions provides a valuable experimental benchmark for fission models that aim to understand this complex decay channel and to predict reaction product yields. Inverse kinematics coupled to the use of a high-resolution spectrometer is shown to be a powerful tool to identify and measure the inclusive isotopic yields of fission fragments. In-flight fusion fission was used to produce secondary beams of neutron-rich isotopes in the collision of a 238U beam at 24 MeV/u with 9Be and 12C targets at GANIL using the LISE3 fragment-separator. Unique A,Z,q identification of fission products was attained with the dE-TKE-Brho-ToF measurement technique. Mass, and atomic number distributions are reported for the two reactions that show the importance of different reaction mechanisms for these two targets., Comment: 14 pages, 10 figures, 4 tables
Published: 2017
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38. Isotopic production cross sections of the residual nuclei in spallation reactions induced by 136Xe projectiles on proton at 500 A MeV

Author: Alain Boudard, Andreas Martin Heinz, T. Enqvist, Enrique Casarejos, F. Farget, Daniela Henzlova, C. Villagrasa, M. Fernández Ordóñez, S. Leray, C. Schmitt, J. Benlliure, B. Fernández-Domínguez, C. Volant, J.E. Ducret, M. V. Ricciardi, K.-H. Schmidt, C. Stéphan, V. Henzl, P. Napolitani, O. Yordanov, L. Tassan-Got, C. Paradela, L. Audouin, D. Pérez-Loureiro, J. Pereira, A. Lafriaskh, A. Kelic-Heil, Juan Antonio Alcantara-Nunez, L. Giot, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear reaction, Nuclear and High Energy Physics, Proton, Nuclear Theory, E = 500 MeV/nucleon, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Residual, Ba presented also in tabular form. Compared with published data at 1000 MeV/nucleon, 7. Clean energy, 01 natural sciences, charge using FRS magnetic spectrometer, Nuclear physics, Momentum, Xe, 0103 physical sciences, longitudinal momentum distributions. Resulting σ for Sn, Spallation, deduced fragment isotopes yields, Cs, Nuclear Experiment, 010306 general physics, Liquid hydrogen, X), Te, Physics, NUCLEAR REACTIONS 1H(136Xe, Spectrometer, measured spallation products mass, 010308 nuclear & particles physics, Projectile, production σ, Physics::Accelerator Physics, Atomic physics, Sb
Abstract: The experiment was performed at the GSI facility in Darmstadt (Germany).; Around 270 medium-mass residual nuclei, formed in spallation reactions induced by 136Xe projectiles impinging on a liquid hydrogen target at 500 AMeV, have been unambiguously identified at GSI using the magnetic spectrometer FRS. The individual production cross sections and the longitudinal momentum distributions have been determined with high accuracy. These data represent an important constraint for theoretical models describing spallation reactions.
Published: 2013
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39. Evolution of triaxial shapes at large isospin: Rh isotopes

Author: A. Navin, M. Rejmund, S. Bhattacharyya, R. Palit, G.H. Bhat, J.A. Sheikh, A. Lemasson, S. Bhattacharya, M. Caamaño, E. Clément, O. Delaune, F. Farget, G. de France, B. Jacquot, Universidade de Santiago de Compostela. Departamento de Física de Partículas, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Variable Energy Cyclotron Centre, Universidade de Santiago de Compostela [Spain] (USC ), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Nuclear and High Energy Physics, Fission, media_common.quotation_subject, SHELL model, Nuclear Theory, Coulomb barrier, Nuclear triaxiality, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Asymmetry, Neutron-rich Rh isotopes, Isotopic identification of fission fragments, 0103 physical sciences, 010306 general physics, Nuclear Experiment, media_common, Physics, Isotope, 010308 nuclear & particles physics, Yrast, lcsh:QC1-999, Triaxial projected shell model, Isospin, Atomic physics, Neutron rich Rh isotopes, lcsh:Physics
Abstract: Expérience GANIL/VAMOS++/EXOGAM; International audience; The rotational response as a function of neutron–proton asymmetry for the very neutron-rich isotopes of Rh (116–119Rh) has been obtained from the measurement of prompt γ rays from isotopically identified fragments, produced in fission reactions at energies around the Coulomb barrier. The measured “signature” splitting of the yrast bands, when compared with the Triaxial Projected Shell Model (TPSM) calculations, shows the need for large, nearly constant, triaxial deformations. The present results are compared with global predictions for the existence of non axial shapes in the periodic table in the case of very neutron-rich nuclei Rh isotopes. The predicted trend of a second local maximum for a triaxial shape around N∼74 is not found.
Published: 2016
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40. Studies on Fission with Aladin

Author: A. Chatillon, Andreas Martin Heinz, Helmut Weick, C. Paradela, Nikolaus Kurz, S. Pietri, DC Gil, G. Boutoux, Bernd Voss, M. Caamaño, Enrique Casajeros, Karl-Heinz Schmidt, Laurent Tassan-Got, J. Benlliure, B. Laurent, L. Grente, G. Belier, Beatriz Jurado, D. Rossi, A. Ebran, Yassid Ayyad, J. F. Martin, T. Gorbinet, Jose-Luis Rodriguez Sanchez, L. Audouin, C. Nociforo, Hector Alvarez Pol, E. Pellereau, J. Taieb, Beatriz Fernandez Dominguez, A. Kelic-Heil, Haik Simon, F. Farget, D. Ramos, J. Vargas, Carme Rodriguez Tajes, Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear physics, Physics, Fission, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ComputingMilieux_MISCELLANEOUS
Abstract: International audience; Note from publisher: This article contains the abstract only.
Published: 2016
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41. Excitation-energy influence at the scission configuration

Author: D. Ramos, C. Rodríguez-Tajes, M. Caamaño, F. Farget, L. Audouin, J. Benlliure, E. Casarejos, E. Clement, D. Cortina, O. Delaune, X. Derkx, A. Dijon, D. Doré, B. Fernández-Domínguez, G. de France, A. Heinz, B. Jacquot, A. Navin, C. Paradela, M. Rejmund, T. Roger, M.-D. Salsac, C. Schmitt, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Joint Research Centre, European Commission, A. Plompen, F.-J. Hambsch, P. Schillebeeckx, W. Mondelaers, J. Heyse, S. Kopecky, P. Siegler, S. Oberstedt, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Nuclear reaction, 010308 nuclear & particles physics, Fission, QC1-999, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Effective nuclear charge, Nuclear physics, Uranium-238, Nuclear fission, 0103 physical sciences, Nuclear fusion, Neutron, Atomic physics, 010306 general physics, Nuclear Experiment, Excitation
Abstract: The conference in EPJ Web of Conferences entitled "ND 2016 International Conference on Nuclear Data for Science and Technology", ISBN: 978-2-7598-9020-0; International audience; Transfer-and fusion-induced fission in inverse kinematics was proven to be a powerful tool to investigate nuclear fission, widening the information of the fission fragments and the access to unstable fissioning systems with respect to other experimental approaches. An experimental campaign for fission investigation has being carried out at GANIL with this technique since 2008. In these experiments, a beam of 238 U, accelerated to 6.1 MeV/u, impinges on a 12 C target. Fissioning systems from U to Cf are populated through transfer and fusion reactions, with excitation energies that range from few MeV up to 46 MeV. The use of inverse kinematics, the SPIDER telescope, and the VAMOS spectrometer permitted the characterization of the fissioning system in terms of mass, nuclear charge, and excitation energy, and the isotopic identification of the full fragment distribution. The neutron excess, the total neutron multiplicity, and the even-odd staggering in the nuclear charge of fission fragments are presented as a function of the excitation energy of the fissioning system. Structure effects are observed at Z∼50 and Z∼55, where their impact evolves with the excitation energy.
Published: 2016
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42. Structural changes at large angular momentum in neutron-richCd121,123

Author: M. Rejmund, A. Navin, S. Bhattacharyya, M. Caamaño, E. Clément, O. Delaune, F. Farget, G. de France, B. Jacquot, and A. Lemasson
Subjects: Physics, Angular momentum, Spectrometer, Isotope, 010308 nuclear & particles physics, Nuclear Theory, SHELL model, 01 natural sciences, Nuclear physics, Matrix (mathematics), 0103 physical sciences, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Excitation, Beam (structure)
Abstract: Prompt γ rays of isotopically identified neutron-rich isotopes of Cd, produced in transfer- and fusion-fission induced by the 238U beam at 6.2 MeV/u on a 9Be target, were measured using the EXOGAM γ -ray detector array and the magnetic spectrometer VAMOS++. New results for the level scheme of 121,123Cd, extending to relatively large angular momentum are reported. The energy levels above 2-MeV excitation energy, are found to differ from those observed in lighter isotopes of Cd indicating a change in structure in these more neutron-rich nuclei. These states are not explained by large-scale shell model calculations, that explain well the structure of the underlying Sn isotopes and the neighboring even-A Cd isotopes. The present data, especially for the odd-A nuclei, point to a deficiency in the matrix elements related to the p-n residual interaction and provide a new domain for testing widely used shell model interactions employed for understanding the evolution of structure in neutron-rich nuclei.
Published: 2016
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43. Electromagnetic properties of neutron-rich nuclei adjacent to the Z=50 shell closure

Author: S. Biswas, M. Caamaño, M. Rejmund, Eric Clément, O. Delaune, A. Navin, Bertrand Jacquot, F. Farget, A. Lemasson, P. Van Isacker, Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Universidade de Santiago de Compostela [Spain] (USC ), Universidade de Santiago de Compostela. Departamento de Física de Partículas, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear and High Energy Physics, In-Sb isotopes, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Isotopic identification, 01 natural sciences, Large isospin and high angular momentum, Investigación::22 Física [Materias], Seniority, 0103 physical sciences, Neutron, 010306 general physics, Nuclear Experiment, Physics, Valence (chemistry), Isotope, 010308 nuclear & particles physics, Yrast, Fission fragments, Spin orbit partners, M1/E2 transitions, lcsh:QC1-999, Pairing, Quadrupole, Atomic physics, Magnetic dipole, lcsh:Physics
Abstract: Low-lying high-spin yrast states in the exotic odd–odd isotopes 124–128Sb (Z=51) and 118–128In (Z=49), studied for the first time, show a striking difference in their observed γ-ray decay. With a single valence proton particle/hole occupying the g7/2/g9/2 spin-orbit partners, dominant electric quadrupole transitions occur in Sb as opposed to magnetic dipole transitions in In. The observed properties are explained on the basis of general principles of symmetry and with large-scale shell-model calculations, and reveal novel aspects of the competition between the neutron–proton interaction and the like-nucleon pairing interaction. Open Access funded by SCOAP³ - Sponsoring Consortium for Open Access Publishing in Particle Physics S.B. acknowledges financial support for her stay at GANIL through the LIA France-India agreement SI
Published: 2016
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44. Studies on fission with ALADIN - Precise and simultaneous measurement of fission yields, total kinetic energy and total promptneutron multiplicity at GSI

Author: Helmut Weick, Andreas Martin Heinz, Haik Simon, Laurent Tassan-Got, J. F. Martin, C. Nociforo, C. Rodriguez-Tajes, A. Kelic-Heil, D. Rossi, A. Chatillon, G. Boutoux, Beatriz Fernandez Dominguez, L. Audouin, J. Benlliure, S. Pietri, L. Grente, C. Paradela, Thomas Aumann, B. Laurent, M. Caamaño, DC Gil, Yassid Ayyad, Bernd Voss, N. Kurz, E. Pellereau, F. Farget, T. Gorbinet, D. Ramos, H. Alvarez-Pol, A. Ebran, J. Taieb, Beatriz Jurado, G. Belier, J. Vargas, Karl-Heinz Schmidt, Jose-Luis Rodríguez-Sànchez, Enrique Casarejos, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Universidade de Santiago de Compostela [Spain] (USC ), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Helmholtz zentrum für Schwerionenforschung GmbH (GSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear reaction, Physics, Nuclear and High Energy Physics, Fission, Nuclear Theory, Fission product yield, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Nuclear physics, Prompt neutron, Nuclear fission, Valley of stability, Nuclear fusion, Neutron, Nuclear Experiment
Abstract: Topical Collection : Perspectives on Nuclear Data for the Next Decade; International audience; A novel technique for fission studies, based on the inverse kinematics approach, is presented. Following pioneering work in the nineties, the SOFIA Collaboration has designed and built an experimental set-up dedicated to the simultaneous measurement of isotopic yields, total kinetic energies and total prompt neutron multiplicities, by fully identifying both fission fragments in coincidence, for the very first time. This experiment, performed at GSI, permits to study the fission of a wide variety of fissioning systems, ranging from mercury to neptunium, possibly far from the valley of stability. A first experiment, performed in 2012, has provided a large array of unprecedented data regarding the nuclear fission process. An excerpt of the results is presented. With this solid starter, further improvements of the experimental set-up are considered, which are consistent with the expected developments at the GSI facility, in order to measure more fission observables in coincidence. The completeness reached in the SOFIA data, permits to scrutinize the correlations between the interesting features of fission, offering a very detailed insight in this still unraveled mechanism.
Published: 2015
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45. Transfer-induced fission in inverse kinematics: Impact on experimental and evaluated nuclear data bases

Author: Enrique Casarejos, J. Benlliure, B. Jurado, Andreas Martin Heinz, L. Gaudefroy, C. Rodriguez-Tajes, F. Farget, X. Derkx, A. Lemasson, Karl-Heinz Schmidt, T. Roger, M. Caamaño, C. Golabek, B. Fernández-Domínguez, C. Schmitt, C. Paradela, O. Delaune, L. Audouin, A. Dijon, D. Cortina, D. Doré, Eric Clément, M. D. Salsac, D. Ramos, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universidade de Santiago de Compostela [Spain] (USC ), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), GANILEXP, Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Nuclear and High Energy Physics, Cluster decay, Proton, Fission, Nuclear Theory, Nuclear data, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, Nuclear physics, Nuclear fission, Neutron number, Nuclear fusion, Atomic number, Atomic physics, Nuclear Experiment
Abstract: Topical collection : Perspectives on Nuclear Dta for the Next Decade; Expérience GANIL/VAMOS; International audience; Inverse kinematics is a new tool to study nuclear fission. Its main advantage is the possibility tomeasure with an unmatched resolution the atomic number of fission fragments, leading to new observablesin the properties of fission-fragment distributions. In addition to the resolution improvement, the studyof fission based on nuclear collisions in inverse kinematics beneficiates from a larger view with respect tothe neutron-induced fission, as in a single experiment the number of fissioning systems and the excitationenergy range are widden. With the use of spectrometers, mass and kinetic-energy distributions may now beinvestigated as a function of the proton and neutron number sharing. The production of fissioning nucleiin transfer reactions allows studying the isotopic yields of fission fragments as a function of the excitationenergy. The higher excitation energy resulting in the fusion reaction leading to the compound nucleus250Cf at an excitation energy of 45MeV is also presented. With the use of inverse kinematics, the chargepolarisation of fragments at scission is now revealed with high precision, and it is shown that it cannotbe neglected, even at higher excitation energies. In addition, the kinematical properties of the fragmentsinform on the deformation configuration at scission
Published: 2015
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46. Accurate measurements of fission-fragment yields in $^{234,235,236,238}$U(γ,f) with the SOFIA set-up

Author: Enrique Casarejos, Y. Yan, N. Kurz, S. Pietri, A. Chatillon, L. Grente, J. Taieb, G. Boutoux, Herbert A. Simon, J. L. Rodriguez-Sanchez, B. Fernández-Domínguez, D. Ramos, J. F. Martin, J. Vargas, D. Cortina-Gil, C. Rodriguez-Tajes, C. Nociforo, C. Paradela, T. Gorbinet, L. Tassan-Got, M. Caamaño, B. Löher, H. Törnqvist, A. Kelic-Heil, H. Alvarez-Pol, E. Pellereau, Helmut Weick, L. Audouin, K.-H. Schmidt, B. Laurent, J. Benlliure, Beatriz Jurado, Yassid Ayyad, F. Farget, Simon Lindberg, Andreas Martin Heinz, G. Belier, D. M. Rossi, Bernd Voss, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Range (particle radiation), Spectrometer, 010308 nuclear & particles physics, Fragment (computer graphics), Fission, Computer science, Physics, QC1-999, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Engineering physics, Coincidence, Nuclear physics, 0103 physical sciences, Physics::Atomic and Molecular Clusters, 010306 general physics, Nuclear Experiment
Abstract: Open Access article distributed under the terms of the Creative Common attribution Licence 4.0; International audience; SOFIA (Studies On Fission with Aladin) is a new experimental setup 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 (γ,f) electromagnetic-induced fission. The SOFIA setup 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 234,235,236,238 U(γ,f) reactions.
Published: 2015
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47. Complete isotopic distributions of fragments produced in transfer- and fusion-induced reactions

Author: Enrique Casarejos, O. Kamalou, J. C. Thomas, O. Delaune, M. G. Saint-Laurent, L. Perrot, C. Schmitt, B. Jurado, C.O. Bacri, A. Navin, Wolfgang Mittig, A. M. Amthor, C. Golabek, F. Farget, A. Lemasson, M. Rejmund, H. Savajols, G. Barreau, Oleg B. Tarasov, C. Stodel, L. Caceres, X. Derkx, J. Pereira, M. Caamano, L. Gaudefroy, J. Benlliure, David J. Morrissey, Karl-Heinz Schmidt, B. Bastin, Antonio Villari, Dominique Bazin, L. Audouin, S. Grévy, B. M. Sherrill, S. M. Lukyanov, B. Blank, T. Roger, B. Fernández-Domínguez, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), PANTECHNIK S.A., Pantechnik, F. Farget, A. Chatillon, H. Faust, G. Fioni, D. Goutte, H. Goutte, Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universidade de Santiago de Compostela [Spain] (USC ), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Aval du cycle et Energie Nucléaire (ACEN), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Noyaux exotiques (NEX), USC, Universidad de Santiago de Compostela, Universidad Santiago de Compostela, Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Fusion, Spectrometer, 010308 nuclear & particles physics, Fission, QC1-999, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Neutron, Atomic physics, 010306 general physics, Nuclear Experiment
Abstract: Expérience GANIL/VAMOS/LISE; International audience; Two fission experiments have been performed at GANIL using 238U beams at different energies and light targets. Different fissioning systems were produced with centre of mass energies from 10 to 240MeV and their decay by fission was investigated with GANIL spectrometers. Fission-fragment isotopic distributions have been obtained. The evolution with impinging energy of their properties, the neutron excess and the width of the neutron-number distributions, gives important insights into the dynamics of the fusionfission mechanism.
Published: 2013
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48. Identification of new transitions and mass assignments of levels inPr143–153

Author: E. H. Wang, A. Lemasson, J. H. Hamilton, A. V. Ramayya, J. K. Hwang, J. M. Eldridge, A. Navin, M. Rejmund, S. Bhattacharyya, S. H. Liu, N. T. Brewer, Y. X. Luo, J. O. Rasmussen, H. L. Liu, H. Zhou, Y. X. Liu, H. J. Li, Y. Sun, F. R. Xu, S. J. Zhu, G. M. Ter-Akopian, Yu. Ts. Oganessian, M. Caamaño, E. Clément, O. Delaune, F. Farget, G. de France, and B. Jacquot
Subjects: Physics, Nuclear and High Energy Physics, Isotope, Fission, Coulomb barrier, Gammasphere, Atomic physics, Coincidence, Spectral line, Spontaneous fission
Abstract: The previously reported levels assigned to 151,152,153Pr have recently been called into question regarding their mass assignment. The above questioned level assignments are clarified by measuring g-transitions tagged with A and Z in an in-beam experiment in addition to the measurements from 252Cf spontaneous fission (SF) and establish new spectroscopic information from $N=84$ to $N=94$ in the Pr isotopic chain. The isotopic chain 143-153Pr has been studied from the spontaneous fission of 252Cf by using Gammasphere and also from the measurement of the prompt g-rays in coincidence with isotopically-identified fission fragments using VAMOS++ and EXOGAM at GANIL. The latter were produced using 238U beams on a 9Be target at energies around the Coulomb barrier. The g-g-g-g data from 252Cf (SF) and those from the GANIL in-beam A- and Z-gated spectra were combined to unambiguously assign the various transitions and levels in 151,152,153Pr and other isotopes. New transitions and bands in 145,147,148,149,150Pr were identified by using g-g-g and g-g-g-g coincidences and A and Z gated g-g spectra. The transitions and levels previously assigned to 151,153Pr have been confirmed by the (A,Z) gated spectra. The transitions previously assigned to 152Pr are now assigned to 151Pr on the basis of the (A,Z) gated spectra. Two new bands with 20 new transitions in 152Pr and one new band with 7 new transitions in 153Pr are identified from the g-g-g-g coincidence spectra and the (A,Z) gated spectrum. In addition, new g-rays are also reported in 143-146Pr. New levels of 145,147-153Pr have been established, reliable mass assignments of the levels in 151,152,153Pr have been reported and new transitions have been identified in 143-146Pr showing the new avenues that are opened by combining the two experimental approaches.
Published: 2015
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49. Lifetime measurments of excited states in neutron-rich fission fragments

Author: T.W. Hagen, L. Grente, A. Görgen, M.-D. Salsac, W. Korten, F. Farget, T. Braunroth, B. Bruyneel, I. Celikovic, E. Clément, G. de France, O. Delaune, A. Dewald, A. Dijon, M. Hackstein, B. Jacquot, J. Litzinger, J. Ljungvall, C. Louchart, C. Michelagnoli, D.R. Napoli, A. Navin, F. Recchia, M. Rejmund, W. Rother, E. Sahin, S. Siem, B. Sulignano, Ch. Theisen, J.J. Valiente-Dobon, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), CSNSM SNO, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM)
Subjects: Physics, Spectrometer, 010308 nuclear & particles physics, Fission, Gamma ray, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, symbols.namesake, Physics and Astronomy (all), Recoil, Excited state, 0103 physical sciences, symbols, Neutron, Atomic number, Atomic physics, Nuclear Experiment, Doppler effect
Abstract: Expérience GANIL/VAMOS/EXOGAM; International audience; Lifetimes of short-lived excited states in a wide range of neutron-richfission fragments were measured using the recoil distance Doppler shift(RDDS) technique, which was applied to fusion-fission reactions in inversekinematics for the first time. The fission fragments were identified eventby-event in mass, charge, and atomic number using the VAMOS magneticspectrometer at GANIL. Gamma rays originating from the fission fragmentswere measured with the EXOGAM array of Ge Clover detectors aroundthe target position. Using a degrader, the change in the Doppler shiftof the $\gamma$ ray allows the application of the RDDS method. Details of theexperimental technique will be discussed and the status for the ongoinganalysis for odd-mass yttrium isotopes will be presented.
Published: 2015
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50. Characterization of the scission point from fission-fragment velocities

Author: A. K. Shrivastava, C. Rodriguez-Tajes, J. Benlliure, O. Delaune, C. Golabek, C.O. Bacri, Enrique Casarejos, C. Schmitt, A. Lemasson, X. Derkx, D. Ramos, M. Caamaño, T. Roger, Karl-Heinz Schmidt, F. Farget, L. Audouin, L. Gaudefroy, Beatriz Jurado, B. Fernández-Domínguez, Universidade de Santiago de Compostela [Spain] (USC ), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universidade de Vigo, University of Liverpool, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), GANILEXP, Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Nuclear and High Energy Physics, Cluster decay, Nuclear Theory, Proton, 010308 nuclear & particles physics, Fission, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Kinetic energy, 01 natural sciences, Nuclear physics, Nuclear Theory (nucl-th), Yield (chemistry), 0103 physical sciences, Atomic number, Atomic physics, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Excitation, Energy (signal processing)
Abstract: The isotopic-yield distributions and kinematic properties of fragments produced in transfer-induced fission of 240Pu and fusion-induced fission of 250Cf, with 9 MeV and 45 MeV of excitation energy respectively, were measured in inverse kinematics with the spectrometer VAMOS. The kinematic properties of identified fission fragments allow to derive properties of the scission configuration such as the distance between fragments, the total kinetic energy, the neutron multiplicity, the total excitation energy, and, for the first time, the proton- and neutron-number sharing during the emergence of the fragments. These properties of the scission point are studied as functions of the fragment atomic number. The correlation between these observables, gathered in one single experiment and for two different fissioning systems at different excitation energies, give valuable information for the understanding and modeling of the fission process., Comment: 12 pages, 8 figures
Published: 2015
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