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1. The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus 133Sb

Author

G. Bocchi, S. Leoni, B. Fornal, G. Colò, P.F. Bortignon, S. Bottoni, A. Bracco, C. Michelagnoli, D. Bazzacco, A. Blanc, G. de France, M. Jentschel, U. Köster, P. Mutti, J.-M. Régis, G. Simpson, T. Soldner, C.A. Ur, W. Urban, L.M. Fraile, R. Lozeva, B. Belvito, G. Benzoni, A. Bruce, R. Carroll, N. Cieplicka-Oryǹczak, F.C.L. Crespi, F. Didierjean, J. Jolie, W. Korten, T. Kröll, S. Lalkovski, H. Mach, N. Mărginean, B. Melon, D. Mengoni, B. Million, A. Nannini, D. Napoli, B. Olaizola, V. Paziy, Zs. Podolyák, P.H. Regan, N. Saed-Samii, B. Szpak, and V. Vedia

Subjects
Neutron induced fission, Gamma spectroscopy, Nuclear state lifetime, Large Ge array, Particle-core couplings, Physics, QC1-999
Abstract

The γ-ray decay of excited states of the one-valence-proton nucleus 133Sb has been studied using cold-neutron induced fission of 235U and 241Pu targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between γ-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 μs isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr3(Ce) scintillators, revealed a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus 132Sn and the valence proton, using the Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin.

Published
2016
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2. Lifetime measurements in $^{182}\hbox {Pt}$ using $\gamma $–$\gamma $ fast-timing

Author

L. Knafla, J.-M. Régis, N. Saed-Samii, C. Müller-Gatermann, C. Fransen, A. Esmaylzadeh, V. Karayonchev, A. Blazhev, R.-B. Gerst, J. Jolie, K. O. Zell, G. Häfner, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Hadron, State (functional analysis), Scintillator, Tandem accelerator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Excited state, 0103 physical sciences, Nuclear fusion, Atomic physics, 010306 general physics, Beam energy, Mixing (physics)
Abstract

The level lifetimes of the $$2_1^+$$ 2 1 + and $$4_1^+$$ 4 1 + states in $$^{182}\hbox {Pt}$$ 182 Pt have been re-measured employing the $$\gamma $$ γ –$$\gamma $$ γ fast-timing technique using fast $$\hbox {LaBr}_3$$ LaBr 3 (Ce) scintillators. Excited states in the nucleus of interest were populated by the fusion-evaporation reaction $$^{170}\hbox {Yb}(^{16}\hbox {O},\hbox {4n})^{182}\hbox {Pt}$$ 170 Yb ( 16 O , 4n ) 182 Pt at a beam energy of 87 MeV provided by the FN Tandem accelerator of the University of Cologne. The lifetime of the $$2_1^+$$ 2 1 + state was re-measured with high accuracy to be $$\tau = 563(12)~$$ τ = 563 ( 12 ) ps and resolves inconsistencies from previous measurements. Experimental results are compared to theoretical calculations in the framework of the sd-IBM with and without configuration mixing.

Published
2021
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3. Lifetime measurements in the odd−A nucleus Hf177

Author

G. Häfner, W. Korten, L. M. Fraile, N. Saed-Samii, A. Esmaylzadeh, Gheorghe Pascovici, Paolo Mutti, J. F. Smith, Zs. Podolyák, W. Urban, Torsten Soldner, Aurelien Blanc, G. S. Simpson, N. Warr, V. Paziy, Ulli Köster, V. Karayonchev, Michael Jentschel, C. A. Ur, C. Townsley, S. Ilieva, Henryk Mach, J. Jolie, A. Vancraeyenest, N. Mǎrginean, L. Knafla, G. Thiamova, Alison Bruce, S. Leoni, J.-M. Régis, S. Lalkovski, P. H. Regan, Petr Alexa, Oliver J. Roberts, and T. Kröll

Subjects
Physics, medicine.anatomical_structure, Spectrometer, 010308 nuclear & particles physics, 0103 physical sciences, Rare earth, Nuclear structure, medicine, Atomic physics, Nanosecond, 010306 general physics, 01 natural sciences, Nucleus
Abstract

Lifetimes of low- and high-spin states in the odd-A nucleus Hf-177 were measured during the EXILL&FATIMA campaign using a spectrometer equipped with eight HPGe-Clover detectors and 16 fast-timing LaBr3(Ce) detectors. For the determination of lifetimes in the pico- to nanosecond regime, the well-established generalized centroid difference method was used. Lifetimes of the 9/2(-), 9/2(+), 11/2(-), 11/2(+) states were remeasured, the lifetimes of the 13/2(-), 17/2(-), 13/2(+), 15/2(+), and 17/2(+) states were determined for the first time and an upper limit for the 19/2(+) state has been established. From these lifetimes absolute reduced transition probabilities were extracted and compared to particle-rotor-model calculations and quasiparticle-phonon-model calculations showing the importance of including multipole-multipole interactions in the description of odd-A nuclei in the rare earth region.

Published
2020
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4. Low- Z boundary of the N=88 –90 shape phase transition: Ce148 near the critical point

Author

Tamara Nikšić, Zs. Podolyák, V. Werner, E. Wilson, P. H. Regan, N. Marginean, Petr Alexa, W. Korten, D. Wilmsen, Ulli Köster, Paolo Mutti, S. Lalkovski, C. Bernards, N. Cooper, Torsten Soldner, C. A. Ur, Oliver J. Roberts, Dario Vretenar, Aurelien Blanc, P. Koseoglou, V. Paziy, T. Kröll, Norbert Pietralla, Michael Jentschel, Zena Patel, M. Thürauf, L. M. Fraile, N. Saed-Samii, Alison Bruce, S. Ilieva, W. Urban, Henryk Mach, J. Jolie, G. S. Simpson, R. B. Cakirli, and J.-M. Régis

Subjects
Physics, Phase transition, 010308 nuclear & particles physics, Fission, Nuclear structure, 7. Clean energy, 01 natural sciences, Coincidence, medicine.anatomical_structure, 13. Climate action, Critical point (thermodynamics), Excited state, 0103 physical sciences, medicine, Atomic physics, 010306 general physics, Spectroscopy, Nucleus
Abstract

Excited states of the neutron-rich nucleus 148Ce have been populated by neutron-induced fission of 235U and 241Pu samples. Their electromagnetic decays were studied by means of γ-ray coincidence spectroscopy with fast-timing capabilities. Lifetimes of the 2+1 and 4+1 states of 148Ce were obtained and their E2 decay rates deduced. The B4=2 = B(E2; 4+1 → 2+1)=B(E2; 2+1 → 0+1) ratio indicates that 148Ce is a transitional nucleus while the N = 88/90 shape phase transition evolves into a gradual change of nuclear deformation for proton numbers Z < 60.

Published
2020
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5. Isomer spectroscopy in Ba133 and high-spin structure of Ba134

Author

E. Farnea, H. K. Wang, C. Fransen, K. Schomacker, A. Gadea, W. Korten, P. Reiter, N. Saed-Samii, A. Jungclaus, L. Corradi, A. Vogt, Hans-Jurgen E. Hess, L. Kaya, K. O. Zell, Suzana Szilner, O. Stezowski, A. Blazhev, J. Eberth, A. Bracco, G. Pollarolo, V. Karayonchev, E. Teruya, B. Birkenbach, A. Esmaylzadeh, T. Mijatović, M. Droste, A. M. Stefanini, N. Shimizu, B. Bruyneel, E. Fioretto, Nunzio Itaco, A. Giaz, Yutaka Utsuno, A. Gottardo, L. Kornwebel, F. Recchia, Zs. Podolyák, F. Scarlassara, R. Menegazzo, S. Leoni, L. Coraggio, A. Gargano, G. Montagnoli, R. Hirsch, F. C. L. Crespi, K. Arnswald, J. Jolie, D. Bazzacco, L. Lewandowski, D. Mengoni, J.-M. Régis, C. Michelagnoli, K. Yanase, E. Sahin, D. R. Napoli, C. Müller-Gatermann, K. Wolf, B. Siebeck, C. A. Ur, K. Hadynska-Klek, M. Seidlitz, S. Lunardi, D. Montanari, M. Siciliano, B. Szpak, G. de Angelis, Andreas Görgen, P. R. John, J. J. Valiente-Dobón, Naotaka Yoshinaga, and P. A. Söderström

Subjects
Physics, Isotope, 010308 nuclear & particles physics, Yrast, 0103 physical sciences, Tandem accelerator, Atomic physics, Spin structure, 010306 general physics, Spectroscopy, 7. Clean energy, 01 natural sciences
Abstract

The transitional nuclei $^{134}$Ba and $^{133}$Ba are investigated after multinucleon transfer employing the high-resolution Advanced GAmma Tracking Array coupled to the magnetic spectrometer PRISMA at the Laboratori Nazionali di Legnaro, Italy, and after fusion-evaporation reaction at the FN tandem accelerator of the University of Cologne, Germany. The Jπ=19/2+ state at 1942 keV in $^{133}$Ba is identified as an isomer with a half-life of 66.6(20)ns corresponding to a B(E1) value of 7.7(4)×10−6e2fm2 for the Jπ=19/2+ to Jπ=19/2− transition. The level scheme of $^{134}$Ba above the Jπ=10+ isomer is extended to approximately 6 MeV. A pronounced backbending is observed at ℏω=0.38 MeV along the positive-parity yrast band. The results are compared to the high-spin systematics of the Z=56 isotopes. Large-scale shell-model calculations employing the GCN50:82, SN100PN, SNV, PQM130, Realistic SM, and EPQQM interactions reproduce the experimental findings and elucidate the structure of the high-spin states. The shell-model calculations employing the GCN50:82 and PQM130 interactions reproduce alignment properties and provide detailed insight into the microscopic origin of this phenomenon in transitional $^{134}$Ba.

Published
2019
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6. The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus 133Sb

Author

B. Fornal, Alison Bruce, G. Benzoni, W. Korten, Raymond J. Carroll, R. Lozeva, Zs. Podolyák, G. Bocchi, A. Nannini, D. R. Napoli, B. Olaizola, Henryk Mach, J. Jolie, D. Mengoni, G. S. Simpson, V. Vedia, D. Bazzacco, Michael Jentschel, F. Didierjean, B. Belvito, N. Saed-Samii, C. A. Ur, N. Cieplicka-Oryǹczak, B. Melon, W. Urban, J.-M. Régis, Torsten Soldner, P. H. Regan, N. Marginean, F. C. L. Crespi, V. Paziy, L. M. Fraile, C. Michelagnoli, B. Szpak, B. Million, T. Kröll, Aurelien Blanc, P. Mutti, A. Bracco, Ulli Köster, Pier Francesco Bortignon, S. Leoni, Gianluca Colò, S. Bottoni, S. Lalkovski, 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 Laue-Langevin (ILL), ILL, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), 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), 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, 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 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)

Subjects
Nuclear and High Energy Physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Nuclear Theory, Large Ge array, Fission, Neutron induced fission, FOS: Physical sciences, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Nuclear Theory (nucl-th), Gamma spectroscopy, Nuclear state lifetime, Particle-core couplings, 0103 physical sciences, medicine, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, Valence (chemistry), 010308 nuclear & particles physics, Yrast, lcsh:QC1-999, medicine.anatomical_structure, Excited state, Física nuclear, Atomic physics, Nucleus, Order of magnitude, lcsh:Physics
Abstract

The gamma-ray decay of excited states of the one-valence-proton nucleus Sb-133 has been studied using cold-neutron induced fission of U-235 and Pu-241 targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between gamma-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 mu s isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr3(Ce) scintillators, revealed a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus Sn-132 and the valence proton, using Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.

Published
2016
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7. Identification of high-spin proton configurations in Ba136 and Ba137

Author

C. Fransen, C. Müller-Gatermann, D. Bazzacco, B. Birkenbach, R. Hetzenegger, C. A. Ur, F. Recchia, R. Hirsch, L. Lewandowski, L. Corradi, Katarzyna Hadynska-Klek, M. Seidlitz, P. R. John, P. Reiter, D. Mengoni, L. Kaya, J. J. Valiente-Dobón, A. Vogt, L. Coraggio, G. Pollarolo, D. Rosiak, W. Korten, E. Sahin, N. Saed-Samii, A. Blazhev, A. Giaz, C. Michelagnoli, A. Jungclaus, E. Farnea, O. Stezowski, A. Gottardo, K. Arnswald, B. Bruyneel, B. Szpak, Nunzio Itaco, Zs. Podolyák, Andreas Görgen, R. Menegazzo, F. Scarlassara, M. Droste, A. M. Stefanini, A. Gargano, J. Jolie, T. Mijatović, M. Weinert, Suzana Szilner, A. Gadea, K. O. Zell, P. A. Söderström, D. R. Napoli, K. Wolf, M. Siciliano, G. Montagnoli, F. C. L. Crespi, S. Lunardi, E. Fioretto, D. Montanari, Hans-Jurgen E. Hess, G. de Angelis, A. Bracco, J. Eberth, and S. Leoni

Subjects
Physics, Proton, Spins, Isotope, 010308 nuclear & particles physics, Nuclear structure, 01 natural sciences, 7. Clean energy, 0103 physical sciences, AGATA, Atomic physics, 010306 general physics, Spin (physics), Spectroscopy, Excitation
Abstract

The high-spin structures of 136Ba and 137Ba are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. 136Ba is populated in a 136Xe+238U MNT reaction employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA at the Laboratori Nazionali di Legnaro, Italy, and in two 9Be + 130Te fusion-evaporation reactions using the High-efficiency Observatory for -Ray Unique Spectroscopy (HORUS) at the FN tandem accelerator of the University of Cologne, Germany. Furthermore, both isotopes are populated in an elusive reaction channel in the 11B+130Te fusion-evaporation reaction utilizing the HORUS -ray array. The level scheme above the J� = 10+ isomer in 136Ba is revised and extended up to an excitation energy of approx. 5.5 MeV. From the results of angular-correlation measurements, the Ex = 3707- and Ex = 4920-keV states are identified as the bandheads of positive- and negative-parity cascades. While the high-spin regimes of both 132Te and 134Xe are characterized by high-energy 12+ ! 10+ transitions, the 136Ba E2 ground-state band is interrupted by negativeparity states only a few hundred keV above the J� = 10+ isomer. Furthermore, spins are established for several hitherto unassigned high-spin states in 137Ba. The new results close a gap along the highspin structure of N < 82 Ba isotopes. Experimental results are compared to large-scale shell-model calculations employing the GCN50:82, Realistic SM, PQM130 and SN100PN interactions. The calculations suggest that the bandheads of the positive-parity bands in both isotopes are predominantly of proton character.

Published
2019
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8. Lifetimes and shape-coexisting states of $^{99}Zr$

Author

J. F. Smith, N. Saed-Samii, R. Lica, G. S. Simpson, V. Werner, L. M. Fraile, C. Bernards, W. Korten, S. Lalkovski, P. H. Regan, T. Kröll, N. Marginean, A. Vancraeyenest, Torsten Soldner, Paolo Mutti, P. Spagnoletti, V. Paziy, F. Drouet, C. Townsley, Marcus Scheck, Liam Gaffney, Henryk Mach, J. Jolie, G Thiamova, M. Zielińska, J.-M. Régis, C. A. Ur, N. Warr, S. Ilieva, Michael Jentschel, S. Kisyov, W. Urban, Aurelien Blanc, Zs. Podolyák, Ulli Köster, D. Ghita, Alison Bruce, C. Larijarni, D. Bucurescu, V. Vedia, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Institut Laue-Langevin (ILL), ILL, 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 Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), 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 Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
Physics, 010308 nuclear & particles physics, Fission, Nuclear structure, Shell (structure), Deformation (meteorology), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Structure, 01 natural sciences, medicine.anatomical_structure, Beamline, Excited state, 0103 physical sciences, Quadrupole, medicine, Física nuclear, Nuclear Physics - Experiment, Atomic physics, 010306 general physics, Nucleus
Abstract

Lifetimes of intermediate-spin states in two rotational bands of 99Zr have been measured. These states were populated following the neutron-induced fission of 235U at the PF1B beamline of the Institut Laue-Langevin, Grenoble, during the EXILL-FATIMA campaign. The nucleus 99Zr59 exhibits shape coexistence and lies precisely on the border of an abrupt change in ground-state deformation when going from N=58 to N=60, making its study interesting for understanding the mechanisms involved in the rapid onset of deformation here. The B(E2) values extracted for decays in the ν3/2[541] band allow quadrupole deformations of β2=0.34(1) and 0.26(3) to be determined for the 821.6- and 1236.6-keV members, whereas β2=0.32(3) was found for the 850.5-keV member of the ν3/2[411]band. Some of the excited states known in 99Zr have been reasonably described with interacting boson-fermion model (IBFM) calculations. Type-II shell evolution is proposed to play a major role in modifying single-particle energies in 99Zr.

Published
2019
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9. Millisecond 23/2+ isomers in the N=79 isotones Xe133 and Ba135

Author

W. Korten, K. O. Zell, A. Vogt, S. Leoni, D. Bazzacco, Nunzio Itaco, F. Recchia, Andreas Görgen, R. Hirsch, Zs. Podolyák, B. Birkenbach, B. Szpak, P. R. John, J. J. Valiente-Dobón, Suzana Szilner, L. Lewandowski, C. Fransen, D. Mengoni, P. A. Söderström, P. Reiter, R. Menegazzo, J. Jolie, G. Pollarolo, E. Fioretto, A. Giaz, E. Farnea, L. Corradi, A. Gottardo, C. A. Ur, L. Kaya, A. Jungclaus, A. Gargano, K. Hadynska-Klek, M. Seidlitz, D. R. Napoli, E. Sahin, K. Wolf, M. Weinert, R. Hetzenegger, J. Eberth, L. Coraggio, S. Lunardi, Hans-Jurgen E. Hess, A. Bracco, C. Müller-Gatermann, D. Montanari, O. Stezowski, G. de Angelis, G. Montagnoli, D. Rosiak, F. C. L. Crespi, M. Siciliano, C. Michelagnoli, M. Droste, A. M. Stefanini, N. Saed-Samii, A. Blazhev, K. Arnswald, B. Bruyneel, F. Scarlassara, T. Mijatović, and A. Gadea

Subjects
Physics, Millisecond, Spectrometer, 010308 nuclear & particles physics, Nuclear structure, Nuclear shell model, Parity (physics), 01 natural sciences, Nuclear physics, 0103 physical sciences, AGATA, 010306 general physics, Spectroscopy, Excitation
Abstract

Detailed information on isomeric states in A ≈ 135 nuclei is exploited to benchmark shell-model calculations in the region northwest of doubly-magic nucleus 132Sn. The N = 79 isotones 133Xe and 135Ba are studied after multinucleon transfer (MNT) in the 136Xe + 208Pb reaction employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA at the Laboratori Nazionali di Legnaro, Italy and in a pulsed-beam experiment at the FN tandem accelerator of the University of Cologne, Germany utilizing a 9Be+130Te fusion-evaporation reaction at a beam energy of 40 MeV. Isomeric states are identified via delayed γ-ray spectroscopy. Hitherto tentative excitation energy, spin, and parity assignments of the 2107-keV Jπ = 23/2+ isomer in 133Xe are confirmed and a half-life of T1/2 = 8.64(13) ms is measured. The 2388-keV state in 135Ba is identified as a Jπ = 23/2+ isomer with a half-life of 1.06(4) ms. The new results show a smooth onset of isomeric Jπ = 23/2+ states along the N = 79 isotones and close a gap in the high-spin systematics towards the recently investigated Jπ = 23/2+ isomer in 139Nd. The resulting systematics of M2 reduced transition probabilities is discussed within the framework of the nuclear shell model. Latest large-scale shell-model calculations employing the SN100PN, GCN50:82, SN100-KTH, and a realistic effective interaction reproduce the experimental findings generally well and give insight into the structure of the isomers.

Published
2018
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10. High-spin structure in the transitional nucleus Xe131 : Competitive neutron and proton alignment in the vicinity of the N=82 shell closure

Author

Naotaka Yoshinaga, W. Korten, A. Bracco, E. Fioretto, Agnese Giaz, Koji Higashiyama, C. A. Ur, F. Recchia, A. Vogt, S. Lunardi, J. Jolie, B. Birkenbach, R. Hirsch, D. Montanari, A. Jungclaus, G. Montagnoli, Suzana Szilner, K. Arnswald, O. Stezowski, B. Bruyneel, G. de Angelis, P. Reiter, F. C. L. Crespi, P. R. John, S. Leoni, B. Fu, T. Steinbach, B. Szpak, E. Farnea, L. Coraggio, A. Gargano, N. Saed-Samii, A. Blazhev, A. Gadea, Roberto Menegazzo, D. Mengoni, M. Siciliano, D. Bazzacco, E. Teruya, M. Queiser, D. Schneiders, Andreas Görgen, A. Gottardo, Fernando Scarlassara, L. Lewandowski, C. Michelagnoli, J. F. Smith, G. Pollarolo, K. Hadynska-Klek, M. Seidlitz, Tea Mijatović, B. Siebeck, J. J. Valiente-Dobón, J. Eberth, C. Müller-Gatermann, E. Sahin, K. O. Zell, D. R. Napoli, K. Wolf, Alberto Pullia, A. M. Stefanini, R. Hetzenegger, P. A. Söderström, D. Rosiak, Nunzio Itaco, Herbert Hess, Zs. Podolyák, C. Fransen, L. Corradi, and L. Kaya

Subjects
Physics, Spectrometer, Isotope, Proton, 010308 nuclear & particles physics, Shell (structure), Nuclear structure, Spin structure, 01 natural sciences, Nuclear physics, 0103 physical sciences, Neutron, AGATA, 010306 general physics
Abstract

The transitional nucleus 131Xe is investigated after multinucleon transfer (MNT) in the 136Xe+208Pb and 136Xe+238U reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA at the Laboratori Nazionali di Legnaro, Italy and as an elusive reaction product in the fusion-evaporation reaction 124Sn(11B,p3n) 131Xe employing the HORUS γ-ray array coupled to a double-sided silicon strip detector (DSSSD) at the University of Cologne, Germany. The level scheme of 131Xe is extended to 5 MeV. A pronounced backbending is observed at ~ω ≈ 0.4 MeV along the negative-parity one-quasiparticle νh11/2(α = −1/2) band. The results are compared to the high-spin systematics of the Z = 54 isotopes and the N = 77 isotones. Large-scale shell-model calculations (LSSM) employing the PQM130, SN100PN, GCN50:82, SN100-KTH and a realistic effective interaction reproduce the experimental findings and provide guidance to elucidate the structure of the high-spin states. Further calculations in 129−132Xe provide insight into the changing nuclear structure along the Xe chain towards the N = 82 shell closure. Proton occupancy in the π 0h11/2 orbital is found to be decisive for the description of the observed backbending phenomenon.

Published
2018
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11. The boundary of the N=90 shape phase transition: 148Ce

Author

P. Koseoglou, V. Werner, N. Pietralla, S. Ilieva, M. Thürauf, C. Bernards, A. Blanc, A. M. Bruce, R. B. Cakirli, N. Cooper, L. M. Fraile, G. de France, M. Jentschel, J. Jolie, U. Koester, W. Korten, T. Kröll, S. Lalkovski, H. Mach, N. Mărginean, P. Mutti, Z. Patel, V. Paziy, Z. Podolyák, P. H. Regan, J.-M. Régis, O. J. Roberts, N. Saed-Samii, G. S. Simpson, T. Soldner, C. A. Ur, W. Urban, D. Wilmsen, E. Wilson, Institut Laue-Langevin (ILL), ILL, 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 Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), 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 National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
Physics, History, Phase transition, Spectrometer, 010308 nuclear & particles physics, Fission, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Computer Science Applications, Education, Semiconductor detector, Critical point (thermodynamics), Picosecond, 0103 physical sciences, Atomic nucleus, ddc:530, Física nuclear, Interacting boson model, Atomic physics, 010306 general physics, Nuclear Experiment
Abstract

Journal of physics / Conference Series Conference Series 1023, 012022 - (2018). doi:10.1088/1742-6596/1023/1/012022, Published by IOP Publ., Bristol

Published
2018
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12. Experimental study of the lifetime and phase transition in neutron-rich Zr98,100,102

Author

O. Stezowski, Tomoaki Togashi, S. Ansari, F. Drouet, N. Saed-Samii, G. S. Simpson, E. Wilson, S. Ilieva, C. A. Ur, W. Korten, V. Paziy, M. D. Salsac, C. Townsley, A. Vancraeyenest, L. M. Fraile, Marcus Scheck, Paolo Mutti, Emyr Clement, B. Olaizola, Henryk Mach, J. Jolie, J.-M. Régis, J. F. Smith, V. Vedia, Oliver J. Roberts, M. Zielińska, Raymond J. Carroll, Zs. Podolyák, W. Urban, Takaharu Otsuka, A. Ignatov, S. Lalkovski, P. H. Regan, N. Marginean, T. Soldner, C. Larijani, Alison Bruce, Yusuke Tsunoda, A.-L. Hartig, T. Kröll, Noritaka Shimizu, Aurelien Blanc, Ulli Köster, N. Warr, and Michael Jentschel

Subjects
Physics, Phase transition, 010308 nuclear & particles physics, Fission, Context (language use), Neutron radiation, 01 natural sciences, 7. Clean energy, Excited state, 0103 physical sciences, Neutron, Atomic physics, Interacting boson model, Nuclear Experiment, 010306 general physics, Line (formation)
Abstract

Rapid shape changes are observed for neutron-rich nuclei with A around 100. In particular, a sudden onset of ground-state deformation is observed in the Zr and Sr isotopic chains at N = 60: Low-lying states in $N\ensuremath{\le}58$ nuclei are nearly spherical, while those with $N\ensuremath{\ge}60$ have a rotational character. Nuclear lifetimes as short as a few picoseconds can be measured using fast-timing techniques with ${\mathrm{LaBr}}_{3}$(Ce) scintillators, yielding a key ingredient in the systematic study of the shape evolution in this region. We used neutron-induced fission of $^{241}\mathrm{Pu}$ and $^{235}\mathrm{U}$ to study lifetimes of excited states in fission fragments in the $A\ensuremath{\sim}100$ region with the EXILL-FATIMA array located at the PF1B cold neutron beam line at the Institut Laue-Langevin. In particular, we applied the generalized centroid difference method to deduce lifetimes of low-lying states for the nuclei $^{98}\mathrm{Zr}$ (N = 58), $^{100}\mathrm{Zr}$, and $^{102}\mathrm{Zr}$ ($N\ensuremath{\ge}60$). The results are discussed in the context of the presumed phase transition in the Zr chain by comparing the experimental transition strengths with the theoretical calculations using the interacting boson model and the Monte Carlo shell model.

Published
2017
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13. High-spin structures in Xe132 and Xe133 and evidence for isomers along the N=79 isotones

Author

V. Karayonchev, E. Teruya, S. Szilner, E. Fioretto, Ching-Yen Wu, T. Mijatović, M. Queiser, N. Saed-Samii, P. Reiter, J. Eberth, A. O. Macchiavelli, S. J. Freeman, W. Gelletly, D. Cline, A. Blazhev, R. Hirsch, R. Teng, Andreas Görgen, A. B. Hayes, J. J. Valiente-Dobón, B. Siebeck, C. J. Pearson, K. Wolf, A. Gadea, Alberto Pullia, B. Birkenbach, Naotaka Yoshinaga, R. S. Chakrawarthy, F. Scarlassara, Agnese Giaz, O. Stezowski, Roberto Menegazzo, J. Jolie, W. Korten, B. Bruyneel, P. A. Söderström, K. Hadynska-Klek, M. Seidlitz, D. Mengoni, A. Gottardo, D. R. Napoli, B. Fu, A. Jungclaus, H. Hua, Robert Chapman, A. M. Stefanini, R. Hetzenegger, S. Lunardi, D. Montanari, E. Farnea, A. Vogt, A. Bracco, C. Wheldon, D. Bazzacco, P. H. Regan, G. Pollarolo, L. Kaya, J.-M. Régis, I. Y. Lee, M. Cromaz, Herbert Hess, C. A. Ur, L. Corradi, C. Michelagnoli, G. de Angelis, K. O. Zell, P. R. John, M. Siciliano, S. Leoni, G. Sletten, F. Recchia, K. Arnswald, G. Montagnoli, Ch. Fransen, C. Müller-Gatermann, Zs. Podolyák, F. C. L. Crespi, D. D. Warner, B. Szpak, J. F. Smith, X. Liang, E. Sahin, and P. Fallon

Subjects
Physics, Crystallography, 010308 nuclear & particles physics, 0103 physical sciences, Gammasphere, AGATA, Atomic physics, 010306 general physics, Spin (physics), 01 natural sciences
Abstract

Author(s): Vogt, A; Siciliano, M; Birkenbach, B; Reiter, P; Hadynska-Klȩk, K; Wheldon, C; Valiente-Dobon, JJ; Teruya, E; Yoshinaga, N; Arnswald, K; Bazzacco, D; Blazhev, A; Bracco, A; Bruyneel, B; Chakrawarthy, RS; Chapman, R; Cline, D; Corradi, L; Crespi, FCL; Cromaz, M; De Angelis, G; Eberth, J; Fallon, P; Farnea, E; Fioretto, E; Fransen, C; Freeman, SJ; Fu, B; Gadea, A; Gelletly, W; Giaz, A; Gorgen, A; Gottardo, A; Hayes, AB; Hess, H; Hetzenegger, R; Hirsch, R; Hua, H; John, PR; Jolie, J; Jungclaus, A; Karayonchev, V; Kaya, L; Korten, W; Lee, IY; Leoni, S; Liang, X; Lunardi, S; MacChiavelli, AO; Menegazzo, R; Mengoni, D; Michelagnoli, C; Mijatovic, T; Montagnoli, G; Montanari, D; Muller-Gatermann, C; Napoli, D; Pearson, CJ; Podolyak, Z; Pollarolo, G; Pullia, A; Queiser, M; Recchia, F; Regan, PH; Regis, JM; Saed-Samii, N; Sahin, E; Scarlassara, F; Seidlitz, M; Siebeck, B; Sletten, G; Smith, JF; Soderstrom, PA; Stefanini, AM; Stezowski, O; Szilner, S; Szpak, B; Teng, R; Ur, C; Warner, DD; Wolf, K; Wu, CY; Zell, KO | Abstract: The transitional nuclei Xe132 and Xe133 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+Pb208 MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the Xe136+Pt198 MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a Te130(α,xn)Xe134-xn fusion-evaporation reaction employing the HORUS γ-ray array at the University of Cologne. The high-spin level schemes are considerably extended above the Jπ=(7-) and (10+) isomers in Xe132 and above the 11/2- isomer in Xe133. The results are compared to the high-spin systematics of the Z=54 as well as the N=78 and N=79 chains. Furthermore, evidence is found for a long-lived (T1/2â‰1μs) isomer in Xe133 which closes a gap along the N=79 isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.

Published
2017
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14. Erratum: Abrupt shape transition at neutron number N=60 : B(E2) values in Sr94,96,98 from fast γ−γ timing [Phys. Rev. C 95 , 054319 (2017)]

Author

J.-M. Régis, J. Jolie, N. Saed-Samii, N. Warr, M. Pfeiffer, A. Blanc, M. Jentschel, U. Köster, P. Mutti, T. Soldner, G. S. Simpson, F. Drouet, A. Vancraeyenest, G. de France, E. Clément, O. Stezowski, C. A. Ur, W. Urban, P. H. Regan, Zs. Podolyák, C. Larijani, C. Townsley, R. Carroll, E. Wilson, L. M. Fraile, H. Mach, V. Paziy, B. Olaizola, V. Vedia, A. M. Bruce, O. J. Roberts, J. F. Smith, M. Scheck, T. Kröll, A.-L. Hartig, A. Ignatov, S. Ilieva, S. Lalkovski, W. Korten, N. Mărginean, T. Otsuka, N. Shimizu, T. Togashi, and Y. Tsunoda

Subjects
Physics, Neutron number, Atomic physics
Published
2017
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15. Abrupt shape transition at neutron number N=60 : B(E2) values in Sr94,96,98 from fast γ−γ timing

Author

J.-M. Régis, J. Jolie, N. Saed-Samii, N. Warr, M. Pfeiffer, A. Blanc, M. Jentschel, U. Köster, P. Mutti, T. Soldner, G. S. Simpson, F. Drouet, A. Vancraeyenest, G. de France, E. Clément, O. Stezowski, C. A. Ur, W. Urban, P. H. Regan, Zs. Podolyák, C. Larijani, C. Townsley, R. Carroll, E. Wilson, L. M. Fraile, H. Mach, V. Paziy, B. Olaizola, V. Vedia, A. M. Bruce, O. J. Roberts, J. F. Smith, M. Scheck, T. Kröll, A.-L. Hartig, A. Ignatov, S. Ilieva, S. Lalkovski, W. Korten, N. Mărginean, T. Otsuka, N. Shimizu, T. Togashi, and Y. Tsunoda

Subjects
Physics, Fission products, Proton, Isotope, 010308 nuclear & particles physics, Fission, Yrast, Nuclear Theory, Monte Carlo method, 7. Clean energy, 01 natural sciences, Nuclear physics, 13. Climate action, Neutron number, 0103 physical sciences, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics
Abstract

Lifetimes of low-lying yrast states in neutron-rich 94,96,98Sr have been measured by Germanium-gated γ−γ fast timing with LaBr3(Ce) detectors using the EXILL&FATIMA spectrometer at the Institut Laue-Langevin. Sr fission products were generated using cold-neutron-induced fission of 235U and stopped almost instantaneously within the thick target. The experimental B(E2) values are compared with results of Monte Carlo shell-model calculations made without truncation on the occupation numbers of the orbits spanned by eight proton and eight neutron orbits and show good agreement. Similarly to the Zr isotopes, the abrupt shape transition in the Sr isotopes near neutron number N=60 is identified as being caused by many-proton excitations to its g9/2 orbit.

Published
2017
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16. Publisher's Note: Half-life of the 15/2+ state of I135 : A test of E2 seniority relations [Phys. Rev. C 95 , 021302(R) (2017)]

Author

W. Korten, V. Vedia, T. Soldner, T. Kroell, Henryk Mach, J. Jolie, U. Koester, Paolo Mutti, P. Spagnoletti, W. Urban, S. Lalkovski, P. H. Regan, N. Marginean, G. S. Simpson, J.-M. Régis, R. Lica, A. Gargano, G. Thiamova, S. Ilieva, Michael Jentschel, L. M. Fraile, A. Vancraeyenest, P. Van Isacker, N. Saed-Samii, Liam Gaffney, Marcus Scheck, Raymond J. Carroll, C. A. Ur, Zs. Podolyák, D. Ghita, C. Townsley, Alison Bruce, V. Paziy, C. Larijani, Aurelien Blanc, and F. Drouet

Subjects
Physics, Seniority, State (functional analysis), Test (assessment), Mathematical physics
Published
2017
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17. Half-life of the15/2+state ofI135: A test ofE2seniority relations

Author

P. Spagnoletti, G. S. Simpson, R. Carroll, J.-M. Régis, A. Blanc, M. Jentschel, U. Köster, P. Mutti, T. Soldner, G. de France, C. A. Ur, W. Urban, A. M. Bruce, F. Drouet, L. M. Fraile, L. P. Gaffney, D. G. Ghită, S. Ilieva, J. Jolie, W. Korten, T. Kröll, C. Larijarni, S. Lalkovski, R. Lică, H. Mach, N. Mărginean, V. Paziy, Zs. Podolyák, P. H. Regan, M. Scheck, N. Saed-Samii, G. Thiamova, C. Townsley, A. Vancraeyenest, V. Vedia, A. Gargano, and P. Van Isacker

Subjects
Physics, 010308 nuclear & particles physics, Component (thermodynamics), Fission, Operator (physics), Half-life, Value (computer science), State (functional analysis), 7. Clean energy, 01 natural sciences, Nuclear physics, medicine.anatomical_structure, 0103 physical sciences, medicine, Seniority, Atomic physics, 010306 general physics, Nucleus
Abstract

The half-life of the 15/2+ 1 state of the 3-valence-proton nucleus 135I has been measured to be 1.74(8) ns using the EXILL-FATIMA mixed array of Ge and LaBr3 detectors. The nuclei were produced following the cold neutron-induced fission of a 235U target at the PF1B beam line of the Institut Laue-Langevin. The extracted B(E2; 15/2+ → 11/2+) value enabled a test of seniority relations for the first time between E2 transition rates. Large-scale shell-model calculations were performed for 134Te and 135I, and reinterpreted in a single-orbit approach. The results show that the two-body component of the E2 operator can be large whereas energy shifts due to the three-body component of the effective interaction are small.

Published
2017
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18. Isomers and high-spin structures in the N=81 isotones Xe135 and Ba137

Author

L. Kaya, M. Siciliano, A. Gengelbach, B. Birkenbach, P. Fallon, Herbert Hess, Agnese Giaz, W. Korten, X. Liang, D. Bazzacco, A. Bracco, Luna Pellegri, V. Vandone, Roberto Menegazzo, S. Lunardi, N. Saed-Samii, B. Bruyneel, M. Bowry, D. Montanari, M. Cromaz, C. Y. Wu, A. Vogt, D. Cline, L. Corradi, P. H. Regan, P. Reiter, A. Blazhev, K. O. Zell, P. R. John, W. Gelletly, K. Arnswald, R. Hirsch, R. Teng, Alberto Pullia, G. Sletten, J. F. Smith, D. Schneiders, E. Sahin, A. Gadea, C. J. Pearson, K. Hadynska-Klek, Robert Chapman, G. Montagnoli, G. Pollarolo, F. Scarlassara, Naotaka Yoshinaga, C. Müller-Gatermann, O. Stezowski, M. Seidlitz, F. Radeck, E. Fioretto, S. Leoni, A. O. Macchiavelli, E. Teruya, T. Mijatović, M. Queiser, G. de Angelis, A. M. Stefanini, J. Eberth, L. Lewandowski, Zs. Podolyák, E. Farnea, A. Gottardo, R. S. Chakrawarthy, D. Rosiak, P. A. Söderström, Andreas Görgen, H. Hua, A. B. Hayes, J. J. Valiente-Dobón, C. Wheldon, D. R. Napoli, K. Geibel, D. Mengoni, B. Fu, J. Jolie, A. Jungclaus, S. Szilner, F. C. L. Crespi, D. D. Warner, S. J. Freeman, T. Steinbach, C. A. Ur, F. Recchia, B. Szpak, Andreas Wiens, I. Y. Lee, C. Michelagnoli, and B. Siebeck

Subjects
Physics, Spectrometer, 010308 nuclear & particles physics, 0103 physical sciences, Quadrupole, SHELL model, Gammasphere, AGATA, Atomic physics, 010306 general physics, Spin (physics), 01 natural sciences
Abstract

The high-spin structures of the N = 81 isotones 135Xe and 137Ba are investigated after multinucleontransfer (MNT) and fusion-evaporation reactions. Both nuclei are populated in (i) 136Xe+238U and (ii) 136Xe+208Pb MNT reactions employing the high-resolution Advanced Gamma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (iii), in the 136Xe+198Pt MNT reaction employing the -ray array GAMMASPHERE in combination with the gas detector array Chico, and (iv) via a 11B+130Te fusion-evaporation reaction. The high-spin level schemes of 135Xe and 137Ba are considerably extended to higher energies. The 2058-keV (19=2 ) state in 135Xe is identified as an isomer, completing the systematics for the N = 81 isotones. Its half-life is measured to be 8.6(10) ns, corresponding to a transition probability of B(E2; 19=2 ! 15=2 ) = 0:539(69) W.u. Latest shell model calculations considering 132Sn as a closed core reproduce the experimental findings and provide guidance to the interpretation of the new levels. The experimentally deduced reduced quadrupole transition probabilities of the isomeric states are compared to shell-model predictions.

Published
2017
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19. Measurement of picosecond lifetimes in neutron-rich Xe isotopes

Author

S. Ilieva, Th. Kröll, J.-M. Régis, N. Saed-Samii, A. Blanc, A. M. Bruce, L. M. Fraile, G. de France, A.-L. Hartig, C. Henrich, A. Ignatov, M. Jentschel, J. Jolie, W. Korten, U. Köster, S. Lalkovski, R. Lozeva, H. Mach, N. Mărginean, P. Mutti, V. Paziy, P. H. Regan, G. S. Simpson, T. Soldner, M. Thürauf, C. A. Ur, W. Urban, N. Warr, Institut Laue-Langevin (ILL), ILL, 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 Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), 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 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)

Subjects
Physics, Isotope, 010308 nuclear & particles physics, Fission, Nuclear Theory, chemistry.chemical_element, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, Xenon, chemistry, Neutron number, Excited state, 0103 physical sciences, Quadrupole, Neutron, Física nuclear, Atomic physics, 010306 general physics, Nuclear Experiment
Abstract

EXILL&FATIMA campaign; International audience; Background: Lifetimes of nuclear excited states in fission fragments have been studied in the past followingisotope separation, thus giving access mainly to the fragments’ daughters and only to long-lived isomeric statesin the primary fragments. For the first time now, short-lived excited states in the primary fragments, producedin neutron-induced prompt fission of 235U and 241Pu, were studied within the EXILL&FATIMA campaign at theintense neutron-beam facility of the Institute Laue-Langevin in Grenoble.Purpose: We aim to investigate the quadrupole collective properties of neutron-rich even-even 138,140,142Xeisotopes lying between the double shell closure N = 82 and Z = 50 and a deformed region with octupolecollectivity.Method: The γ rays emitted from the excited fragments were detected with a mixed array consisting of 8 HPGeEXOGAM Clover detectors (EXILL) and 16 LaBr3(Ce) fast scintillators (FATIMA). The detector system hasthe unique ability to select the interesting fragment making use of the high resolution of the HPGe detectorsand determine subnanosecond lifetimes using the fast scintillators. For the analysis the generalized centroiddifference method was used.Results: We show that quadrupole collectivity increases smoothly with increasing neutron number above theclosed N = 82 neutron shell. Our measurements are complemented by state-of-the-art theory calculations basedon shell-model descriptions.Conclusions: The observed smooth increase in quadrupole collectivity is similar to the evolution seen in themeasured masses of the xenon isotopic chain and is well reproduced by theory. This behavior is in contrast tohigher Z even-even nuclei where abrupt change in deformation occurs around N = 90.

Published
2016
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20. Evolution ofE2transition strength in deformed hafnium isotopes from new measurements onHf172,Hf174, andHf176

Author

J.-M. Régis, S. Stegemann, M. Rudigier, K. O. Zell, Kosuke Nomura, R.-B. Gerst, J. Jolie, L. M. Robledo, N. Saed-Samii, A. Blazhev, N. Warr, R. R. Rodríguez-Guzmán, C. Fransen, and M. Dannhoff

Subjects
Physics, Nuclear and High Energy Physics, Isotope, chemistry.chemical_element, Coulomb excitation, Hafnium, symbols.namesake, chemistry, Picosecond, symbols, Interacting boson model, Atomic physics, Spectroscopy, Hamiltonian (quantum mechanics), Boson
Abstract

Background: The available data for $E2$ transition strengths in the region between neutron-deficient hafnium and platinum isotopes are far from complete. More and precise data are needed to enhance the picture of structure evolution in this region and to test state-of-the-art nuclear models. In a simple model, the maximum collectivity is expected at the middle of the major shell. However, for actual nuclei, particularly in heavy-mass regions, which should be highly complex, this picture may no longer be the case, and one should use a more realistic nuclear-structure model. We address this point by studying the spectroscopy of Hf as a representative case.Purpose: We remeasure the ${2}_{1}^{+}$ half-lives of $^{172,174,176}\mathrm{Hf}$, for which there is some disagreement in the literature. The main goal is to measure, for the first time, the half-lives of higher-lying states of the rotational band. The new results are compared to a theoretical calculation for absolute transition strengths.Method: The half-lives were measured using $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ and conversion-electron-$\ensuremath{\gamma}$ delayed coincidences with the fast timing method. For the determination of half-lives in the picosecond region, the generalized centroid difference method was applied. For the theoretical calculation of the spectroscopic properties, the interacting boson model is employed, whose Hamiltonian is determined based on microscopic energy-density functional calculations.Results: The measured ${2}_{1}^{+}$ half-lives disagree with results from earlier $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ fast timing measurements, but are in agreement with data from Coulomb excitation experiments and other methods. Half-lives of the ${4}_{1}^{+}$ and ${6}_{1}^{+}$ states were measured, as well as a lower limit for the ${8}_{1}^{+}$ states.Conclusions: This work shows the importance of a mass-dependent effective boson charge in the interacting boson model for the description of $E2$ transition rates in chains of nuclei. It encourages further studies of the microscopic origin of this mass dependence. New experimental values on transition rates in nuclei from neighboring isotopic chains could support these studies.

Published
2015
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21. Lifetime measurement in neutron-rich A~100 nuclei

Author

Oliver J. Roberts, L. M. Fraile, W. Korten, Takaharu Otsuka, E. Wilson, N. Warr, O. Stezowski, M. Zielińska, Aurelien Blanc, Ulli Köster, F. Drouet, Tomoaki Togashi, W. Urban, Paolo Mutti, Torsten Soldner, S. Ansari, J.-M. Régis, Michael Jentschel, Yusuke Tsunoda, T. Kröll, N. Saed-Samii, C. A. Ur, S. Ilieva, V. Paziy, Noritaka Shimizu, C. Townsley, Henryk Mach, J. Jolie, G. S. Simpson, A.-L. Hartig, J. F. Smith, M. D. Salsac, A. Vancraeyenest, C. Larijani, Marcus Scheck, Eric Clément, Raymond J. Carroll, A. Ignatov, Alison Bruce, Zs. Podolyák, S. Lalkovski, P. H. Regan, N. Marginean, V. Vedia, B. Olaizola, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Laue-Langevin (ILL), ILL, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), 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 de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), 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)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, 010308 nuclear & particles physics, Fission, QC1-999, SHELL model, Monte Carlo method, Nuclear Theory, Centroid, Deformation (meteorology), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, Nuclear physics, Excited state, 0103 physical sciences, Neutron, 010306 general physics, Nuclear Experiment
Abstract

Lifetimes of excited states of the 98;100;102Zr nuclei were measured by using the Generalized Centroid Difference Method. The nuclei of interest were populated via neutron-induced fission of 241Pu and 235U during the EXILL-FATIMA campaign. The obtained lifetimes were used to calculate the B(E2) transition strengths and β deformation parameters which were then compared with the recent theoretical predictions obtained with Monte Carlo Shell Model.

Published
2018
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22. The γ-γ fast-timing technique and the EXILL&FATIMA campaign

Author

J.-M. Régis, G.S. Simpson, H. Mach, A. Blanc, M. Jentschel, U. Köster, P. Mutti, T. Soldner, G. de France, C.A. Ur, W. Urban, J. Jolie, N. Saed-Samii, N. Warr, L.M. Fraile, V. Paziy, P.H. Regan, Zs. Podolyák, S. Lalkovski, A.M. Bruce, T. Kröll, W. Korten, and N. Marginean

Subjects
Physics, Fission products, 010308 nuclear & particles physics, Fission, QC1-999, Detector, Centroid, 01 natural sciences, Spectral line, Semiconductor detector, Nuclear physics, Excited state, 0103 physical sciences, Nuclear Experiment, 010306 general physics, Spectroscopy
Abstract

At the Institut Laue-Langevin in Grenoble, germanium-gated γ-γ fast-timing lifetime measurements of nuclear excited states in neutron-rich nuclei have been performed within a prompt γ-ray spectroscopy experimental campaign. We report on results obtained from the cold-neutron induced fission of 235 U. The excited secondary fission products were stopped almost instantaneously within the thick target and the γ rays emitted were collected triggerlessly using the EXILL&FATIMA mixed array of HPGe and LaBr 3 (Ce) detectors. Precise lifetimes could be determined by analysing the γ-γ time difference spectra using the generalized centroid difference method. This picosecondsensitive method provides many advantages and is briefly explained. Still, the major source of systematic errors is related to the contribution of time-correlated Compton background. The EXILL&FATIMA results are discussed with respect to the typical energy-dependent timing behaviour of the background. According to the time response of the background, appropriate methods and a time correction for the sub-nanosecond regime are proposed.

Published
2018
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23. The (n,γ) campaigns at EXILL

Author

R. Lica, S. Kisyov, W. Urban, D. Curien, M. Zielinska, G. Bocchi, M. Czerwinski, Michael Jentschel, M. Pfeiffer, Henryk Mach, J. Jolie, G. Benzoni, G.S. Simpson, B. Szpak, N. Saed-Samii, S. Leoni, D. Ivanova, W. Korten, R. Leguillon, P. H. Regan, N. Marginean, S. Lalkovski, C. Bernards, N. Cieplicka, P. G. Thirolf, L. Sengele, S. Bottoni, T. Rzaca-Urban, R. B. Cakirli, Paolo Mutti, Ralph Massarczyk, S. Ilieva, C. Lorenz, Dietrich Habs, A. Korgul, P. Ba̧czyk, R. F. Casten, Marcus Scheck, N. Warr, Oliver J. Roberts, Ulli Köster, L. M. Fraile, C. M. Petrache, J.-M. Régis, F. C. L. Crespi, V. Paziy, Zs. Podolyák, A. Ignatov, Th. Kröll, B. Fornal, D. Wilmsen, Alison Bruce, R. Lozeva, T. Soldner, S. Ahmed, M. D. Salsac, A. Vancraeyenest, C. A. Ur, V. Werner, C. Mazzocchi, F. Drouet, Ronald Schwengner, M. Thürauf, Aurelien Blanc, R. John, and N. Cooper

Subjects
Nuclear physics, Physics, Astrophysics::High Energy Astrophysical Phenomena, QC1-999, Astrophysics, Neutron radiation, Scintillator, Coincidence, Collimated light
Abstract

At the PF1B cold neutron beam line at the Institut Laue Langevin, the EXILL array consisting of EXOGAM, GASP and ILL-Clover detectors was used to perform (n,$\gamma$) measurements at very high coincidence rates. About ten different reactions were measured in autumn 2012 using a highly collimated cold neutron beam. In spring 2013, the EXOGAM array was combined with 16 LaBr3(Ce) scintillators in the EXILL&FATIMA campaign for the measurement of lifetimes using the generalised centroid difference method. We report on the properties of the set-ups and present first results from both campaigns.

Published
2015

24. B(E2;21+→01+)value inKr90

Author

J.-M. Régis, J. Jolie, N. Saed-Samii, N. Warr, M. Pfeiffer, A. Blanc, M. Jentschel, U. Köster, P. Mutti, T. Soldner, G. S. Simpson, F. Drouet, A. Vancraeyenest, G. de France, E. Clément, O. Stezowski, C. A. Ur, W. Urban, P. H. Regan, Zs. Podolyák, C. Larijani, C. Townsley, R. Carroll, E. Wilson, L. M. Fraile, H. Mach, V. Paziy, B. Olaizola, V. Vedia, A. M. Bruce, O. J. Roberts, J. F. Smith, T. Kröll, A.-L. Hartig, A. Ignatov, S. Ilieva, M. Thürauf, S. Lalkovski, D. Ivanova, S. Kisyov, W. Korten, M.-D. Salsac, M. Zielińska, N. Mărginean, D. G. Ghită, R. Lică, C. M. Petrache, A. Astier, and R. Leguillon

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, 0103 physical sciences, Atomic physics, 010306 general physics, 01 natural sciences, Sudden onset
Abstract

A smooth onset of collectivity in ${}^{88,92,94,96}\mathrm{Kr}$ has been determined from reported $B(E2;{2}_{1}^{+}\ensuremath{\rightarrow}{0}_{1}^{+})$ and $E({2}_{1}^{+})$ values. This is in contrast to the sudden onset in even-even Zr, Mo, and Sr isotopes. Our objective was to complete the systematics by determining the $B(E2;{2}_{1}^{+}\ensuremath{\rightarrow}{0}_{1}^{+})$ value in $^{90}\mathrm{Kr}$, which was produced by cold-neutron-induced fission of ${}^{235}\mathrm{U}$. The lifetime of the ${2}_{1}^{+}$ state in $^{90}\mathrm{Kr}$ was measured via the electronic $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ timing technique using the EXILL and FATIMA spectrometers. Based on the measured mean lifetime of $\ensuremath{\tau}$ = 15(10) ps, the $B(E2;{2}_{1}^{+}\ensuremath{\rightarrow}{0}_{1}^{+})$ value of $13{}_{\ensuremath{-}5}^{+26}$ W.u. in $^{90}\mathrm{Kr}$ is determined for the first time and the smooth onset of deformation in the even-even Kr isotopes beyond neutron number $N=50$ is confirmed.

Published
2014
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25. Lifetime Measurements in Neutron-rich Xe Isotopes - Evolution of Quadrupole Collectivity Beyond $^{132}$Sn

Author

S. Ilieva, S. Bönig, A.-L. Hartig, C. Henrich, A. Ignatov, Th. Kröll, M. Thürauf, J. Jolie, J.-M. Régis, N. Saed-Samii, A. Blanc, G. de France, M. Jentschel, U. Köster, P. Mutti, G. S. Simpson, T. Soldner, W. Urban, N. Mǎrginean, C. A. Ur, H. Mach, L. M. Fraile, V. Paziy, P. H. Regan, A. M. Bruce, S. Lalkovski, W. Korten, Institut Laue-Langevin (ILL), 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), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
Isotope, Chemistry, Fission, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Lifetimes of excited states, quadrupole collectivity, neutron-rich Xe isotopes, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear physics, Picosecond, Excited state, Quadrupole, Neutron, MAGIC (telescope), Atomic physics, Nuclear Experiment, Spectroscopy
Abstract

EXILL&FATIMA and IS411 collaborations; International audience; Picosecond lifetimes of excited states in neutron-rich Xe isotopes were measured at the Institut Laue-Langevin via $\gamma$-ray spectroscopy of fission fragments from neutron-induced fission of 235U and 241Putargets. The data collected with the recently installed fast timing array FATIMA in combination withthe EXOGAM Ge array were analysed using the new generalized centroid difference method. Ouraim is to study the quadrupole and octupole collectivity, arising in the mass region beyond the doublymagic 132Sn, by means of transition probabilities. These can be calculated from the directly measuredlifetimes.

Published
2014
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26. The Generalized Centroid Difference method for lifetime measurements viaγ-γcoincidences using large fast-timing arrays

Author

F. Drouet, Zs. Podolyák, Aurelien Blanc, Alison Bruce, O. Stezowski, Gheorghe Pascovici, T. Kröll, W. Korten, T. Soldner, J.-M. Régis, S. Mărginean, Henryk Mach, N. Warr, Ulli Köster, J. Jolie, P.H. Regan, M. Rudigier, Paolo Mutti, G.S. Simpson, W. Urban, Michael Jentschel, V. Paziy, S. Lalkovski, M. Pfeiffer, C. A. Ur, A. Vancraeyenest, S. Ilieva, L. M. Fraile, N. Saed-Samii, A. Blazhev, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), ILL, 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), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-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), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, business.industry, QC1-999, Detector, Centroid, Observable, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Scintillator, Spectral line, Computational physics, Superposition principle, Optics, Cascade, Excited state, business
Abstract

This is an Open Access article distributed under the terms of the Creative Common Attribution Licence 4.0 which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.; International audience; A novel method for direct electronic "fast-timing" lifetime measurements of nuclear excited statesvia γ-γ coincidences using an array equipped with N very fast high-resolution LaBr3(Ce) scintillator detectorsis presented. The generalized centroid difference method provides two independent “start” and “stop” timespectra obtained without any correction by a superposition of the N(N − 1)/2 calibrated γ-γ time differencespectra of the N detector fast-timing system. The two fast-timing array time spectra correspond to a forwardand reverse gating of a specific γ-γ cascade and the centroid difference as the time shift between the centroidsof the two time spectra provides a picosecond-sensitive mirror-symmetric observable of the set-up. The energydependentmean prompt response difference between the start and stop events is calibrated and used as a singlecorrection for lifetime determination. These combined fast-timing array mean γ-γ zero-time responses can bedetermined for 40 keV < Eγ < 1.4 MeV with a precision better than 10 ps using a 152Eu γ-ray source. Thenew method is described with examples of (n,γ) and (n,f,γ) experiments performed at the intense cold-neutronbeam facility PF1B of the Institut Laue-Langevin in Grenoble, France, using 16 LaBr3(Ce) detectors withinthe EXILL&FATIMA campaign in 2013. The results are discussed with respect to possible systematic errorsinduced by background contributions.

Published
2015
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27. First results of the (n,γ) EXILL campaigns at the Institut Laue Langevin using EXOGAM and FATIMA

Author

J Jolie, J-M Régis, D Wilmsen, S Ahmed, M Pfeiffer, N Saed-Samii, N Warr, A Blanc, M Jentschel, U Köster, P Mutti, T Soldner, G Simpson, G de France, W Urban, A M Bruce, O J Roberts, L M Fraile, V Paziy, A Ignatov, S Ilieva, Th Kröll, M Scheck, M Thürauf, D Ivanova, S Kisyov, S Lalkovski, Zs Podolyak, P H Regan, W Korten, D Habs, P G Thirolf, C A Ur, Institut Laue-Langevin (ILL), ILL, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-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), EXOGAM, 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 physics, History, Optics, business.industry, Scintillator, Neutron radiation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], business, Computer Science Applications, Education
Abstract

At the PF1B cold neutron beam line at the Institut Laue Langevin the EXILL array consisting of EXOGAM, GASP and LOHENGRIN detectors was used to perform (n,γ) measurements under very high coincidence rates. About ten different reactions were then measured in autumn 2012. In spring 2013 the EXOGAM array was combined with 16 LaBr3(Ce) scintillators in the FATIMA@EXILL campaign for the measurement of lifetimes using the generalised centroid difference method. We report on the properties of both set-ups and present first results on Pt isotopes from both campaigns.

Published
2014
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