| Records |
| Author |
Banik, R. et al; Perez-Vidal, R.M. |
| Title |
High-spin states above the isomers in neutron-rich iodine nuclei near N=82 |
Type |
Journal Article |
| Year |
2020 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
102 |
Issue |
4 |
Pages |
044329 - 15pp |
| Keywords |
|
| Abstract |
Excited states of neutron-rich iodine isotopes I130-134 above the high-spin isomers have been identified using prompt-delayed gamma-ray spectroscopy. The iodine isotopes were produced as fission fragments of fusion-fission and transfer induced fission of 9Be(U-238, f) at a beam energy of 6.2 MeV/u. The complete (A, Z) identification was obtained using the large acceptance magnetic spectrometer VAMOS++. The AGATA gamma-ray tracking array was used to detect the prompt gamma rays while the delayed gamma rays (in the time range of 100 ns to 200 μs) from the isomeric states were identified by the EXOGAM segmented clover detectors, placed behind the focal plane of the VAMOS++ spectrometer. The high-spin states above the (8(-)) isomers in I-130,I-132 were populated for the first time, and a new isomer in I-132 was identified. A new gamma-ray transition was also assigned to the level structure of I-134. Prompt transitions above the 19/2- isomer were identified in I-131,I-133, for the first time. The level structures are interpreted in terms of the systematics of odd-Z nuclei above the Z = 50 shell closure and large-scale shell model calculations. |
Address  |
[Banik, R.; Bhattacharyya, S.; Bhattacharya, Soumik; Mukherjee, G.] Variable Energy Cyclotron Ctr, 1-AF Bidhannagar, Kolkata 700064, India, Email: sarmi@vecc.gov.in |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000583198600001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4588 |
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| Author |
Biswas, S. et al; Perez-Vidal, R.M.; Domingo-Pardo, C. |
| Title |
Effects of one valence proton on seniority and angular momentum of neutrons in neutron-rich(51)( 122-)(131)Sb isotopes |
Type |
Journal Article |
| Year |
2019 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
99 |
Issue |
6 |
Pages |
064302 - 21pp |
| Keywords |
|
| Abstract |
Background: Levels fulfilling the seniority scheme and relevant isomers are commonly observed features in semimagic nuclei; for example, in Sn isotopes (Z = 50). Seniority isomers in Sn, with dominantly pure neutron configurations, directly probe the underlying neutron-neutron (vv) interaction. Furthermore, an addition of a valence proton particle or hole, through neutron-proton (v pi) interaction, affects the neutron seniority as well as the angular momentum. Purpose: Benchmark the reproducibility of the experimental observables, like the excitation energies (E-x) and the reduced electric-quadrupole transition probabilities [B(E2)], with the results obtained from shell-model interactions for neutron-rich Sn and Sb isotopes with N < 82. Study the sensitivity of the aforementioned experimental observables to the model interaction components. Furthermore, explore from a microscopic point of view the structural similarity between the isomers in Sn and Sb, and thus the importance of the valence proton. Methods: The neutron-rich Sb122-131 isotopes were produced as fission fragments in the reaction Be-9(U-238, f) with 6.2 MeV/u beam energy. A unique setup, consisting of AGATA, VAMOS++, and EXOGAM detectors, was used which enabled the prompt-delayed gamma-ray spectroscopy of fission fragments in the time range of 100 ns to 200 μs. Results: New isomers and prompt and delayed transitions were established in the even-A Sb122-131 isotopes. In the odd-A Sb122-131 isotopes, new prompt and delayed gamma-ray transitions were identified, in addition to the confirmation of the previously known isomers. The half-lives of the isomeric states and the B(E2) transition probabilities of the observed transitions depopulating these isomers were extracted. Conclusions: The experimental data was compared with the theoretical results obtained in the framework of large-scale shell-model (LSSM) calculations in a restricted model space. Modifications of several components of the shell-model interaction were introduced to obtain a consistent agreement with the excitation energies and the B(E2) transition probabilities in neutron-rich Sn and Sb isotopes. The isomeric configurations in Sn and Sb were found to be relatively pure. Furthermore, the calculations revealed that the presence of a single valence proton, mainly in the g(7/2) orbital in Sb isotopes, leads to significant mixing (due to the v pi interaction) of (i) the neutron seniorities (upsilon(v)) and (ii) the neutron angular momentum (I-v). The above features have a weak impact on the excitation energies, but have an important impact on the B(E2) transition probabilities. In addition, a constancy of the relative excitation energies irrespective of neutron seniority and neutron number in Sn and Sb was observed. |
| Address |
[Biswas, S.; Lemasson, A.; Rejmund, M.; Navin, A.; Kim, Y. H.; Michelagnoli, C.; Clement, E.; de France, G.; Fremont, G.; Goupil, J.; Jacquot, B.; Li, H. J.; Menager, A.; More, V; Ropert, J.; Lefevre, A.; Saillant, F.] CNRS, GANIL, CEA, IN2P3,DRF, Bd Henri Becquerel,BP 55027, F-14076 Caen 5, France, Email: biswas@ganil.fr; |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000470856500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4051 |
| Permanent link to this record |
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| |
| Author |
Biswas, S. et al; Perez-Vidal, R.M. |
| Title |
Prompt-delayed gamma-ray spectroscopy of neutron-rich In-119, In-121 isotopes |
Type |
Journal Article |
| Year |
2020 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
102 |
Issue |
1 |
Pages |
014326 - 10pp |
| Keywords |
|
| Abstract |
Background: The Z = 50 shell closure, near N = 82, is unique in the sense that it is the only shell closure with the spin-orbit partner orbitals, pi g(9/2) and pi g(7/2), enclosing the magic gap. The interaction of the proton hole/particle in the above-mentioned orbitals with neutrons in the nu h(11)(/2) orbital is an important prerequisite to the understanding of the nuclear structure near N = 82 and the nu pi interaction. Purpose: To explore the structural similarity between the high-spin isomeric states in In (Z = 49), Sn (Z = 50), and Sb (Z = 51) isotopes from a microscopic point of view. In addition, to understand the role of a proton hole or particle in the spin-orbit partner orbitals, pi g(9/2) and pi g(7/2), respectively, with neutron holes in the nu h(11)(/2) orbital on these aforementioned isomers. Methods: The fusion and transfer induced fission reaction Be-9(U-238, f) with 6.2 MeV/u beam energy, using a unique setup consisting of AGATA, VAMOS ++, and EXOGAM detectors, was used to populate through the fission process and study the neutron-rich In-119,In-121 isotopes. This setup enabled the prompt-delayed gamma-ray spectroscopy of isotopes in the time range of 100 ns-200 μs. Results: In the odd-A In-119,In-121 isotopes, indications of a short half-life 19/2(-) isomeric state, in addition to the previously known 25/2(+) isomeric state, were observed from the present data. Further, new prompt transitions above the 25/2(+) isomer in In-121 were identified along with reevaluation of its half-life. Conclusions: The experimental data were compared with the theoretical results obtained in the framework of large-scale shell-model calculations in a restricted model space. The <pi g(9/2)nu h(11/2); I vertical bar H vertical bar pi g(9/2) nu h(11/2);I > two-body matrix elements of residual interaction were modified to explain the excitation energies and the B(E2) transition probabilities in the neutron-rich In isotopes. The (i) decreasing trend of E(29/2(+))-E(25/2(+)) in odd-In (with dominant configuration pi g(9/)(2)(-1) nu h(11/2)(-2) and maximum aligned spin of 29/2+) and (ii) increasing trend of E(27/2(+)) – E(23/2(+)) in odd-Sb (with dominant configuration pi g(7/)(2)(+1) nu h(11/2)(-2) and maximum aligned spin of 27/2(+)) with increasing neutron number could be understood as a consequence of hole-hole and particle-hole interactions, respectively. |
| Address |
[Biswas, S.; Lemasson, A.; Rejmund, M.; Navin, A.; Kim, Y. H.; Michelagnoli, C.; Clement, E.; de France, G.; Fremont, G.; Goupil, J.; Jacquot, B.; Li, H. J.; Menager, L.; Morel, V; Ropert, J.] GANIL, CEA, DRF, CNRS,IN2P3, Bd Henri Becquerel,BP 55027, F-14076 Caen 05, France, Email: lemasson@ganil.fr |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
|
| ISSN |
0556-2813 |
ISBN |
|
Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000556554700003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4489 |
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| Author |
Boso, A. et al; Domingo-Pardo, C.; Perez-Vidal, R.M. |
| Title |
Isospin dependence of electromagnetic transition strengths among an isobaric triplet |
Type |
Journal Article |
| Year |
2019 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
797 |
Issue |
|
Pages |
134835 - 6pp |
| Keywords |
|
| Abstract |
Electric quadrupole matrix elements, M-p, for the J(pi) = 2(+) -> 0(+), Delta T = 0, T = 1 transitions across the A = 46 isobaric multiplet Cr-46-V-46-Ti-46 have been measured at GSI with the FRS-LYCCA-AGATA setup. This allows direct insight into the isospin purity of the states of interest by testing the linearity of M-p with respect to T-z. Pairs of nuclei in the T = 1 triplet were studied using identical reaction mechanisms in order to control systematic errors. The M-p values were obtained with two different methodologies: (i) a relativistic Coulomb excitation experiment was performed for Cr-46 and Ti-46; (ii) a “stretched target” technique was adopted here, for the first time, for lifetime measurements in V-46 and Ti-46. A constant value of M-p across the triplet has been observed. Shell-model calculations performed within the fp shell fail to reproduce this unexpected trend, pointing towards the need of a wider valence space. This result is confirmed by the good agreement with experimental data achieved with an interaction which allows excitations from the underlying sd shell. A test of the linearity rule for all published data on complete T = 1 isospin triplets is presented. |
| Address |
[Boso, A.; Recchia, F.; Lenzi, S. M.; John, P. R.; Grassi, L.; Mengoni, D.] Univ Padua, Dipartimento Fis & Astron Galileo Galilei, I-35131 Padua, Italy, Email: michael.bentley@york.ac.uk |
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Thesis |
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| Publisher |
Elsevier |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0370-2693 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000488071200023 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4158 |
| Permanent link to this record |
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| Author |
AGATA Collaboration (Cederwall, B. et al); Gadea, A.; Jurado, M.; Domingo-Pardo, C.; Huyuk, T.; Perez-Vidal, R.M. |
| Title |
Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus Ru-88 |
Type |
Journal Article |
| Year |
2020 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
124 |
Issue |
6 |
Pages |
062501 - 6pp |
| Keywords |
|
| Abstract |
The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N = Z) nuclide Ru-88(44)44 has been measured using the combination of the Advanced Gamma Tracking Array (AGATA) spectrometer, the NEDA and Neutron Wall neutron detector arrays, and the DIAMANT charged particle detector array. Excited states in Ru-88 were populated via the Fe-54(Ar-36, 2n gamma)Ru-88* fusion-evaporation reaction at the Grand Accelerateur National d'Ions Lourds (GANIL) accelerator complex. The observed gamma-ray cascade is assigned to Ru-88 using clean prompt gamma-gamma-2-neutron coincidences in anticoincidence with the detection of charged particles, confirming and extending the previously assigned sequence of low-lying excited states. It is consistent with a moderately deformed rotating system exhibiting a band crossing at a rotational frequency that is significantly higher than standard theoretical predictions with isovector pairing, as well as observations in neighboring N > Z nuclides. The direct observation of such a “delayed” rotational alignment in a deformed N = Z nucleus is in agreement with theoretical predictions related to the presence of strong isoscalar neutron-proton pair correlations. |
| Address |
[Cederwall, B.; Liu, X.; Aktas, O.; Ertoprak, A.; Zhang, W.; Qi, C.; Nyberg, A. Atac; Back, T.; Doncel, M.; Gottardo, A.] KTH Royal Inst Technol, S-10691 Stockholm, Sweden, Email: cederwall@nuclear.kth.se |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-9007 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000513242500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4278 |
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| Author |
Ciemala, M. et al; Domingo-Pardo, C.; Perez-Vidal, R.M. |
| Title |
Testing ab initio nuclear structure in neutron-rich nuclei: Lifetime measurements of second 2(+) state in C-16 and O-20 |
Type |
Journal Article |
| Year |
2020 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
101 |
Issue |
2 |
Pages |
021303 - 7pp |
| Keywords |
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| Abstract |
To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2(+) state in neutron-rich O-20, tau(2(2)(+)) = 150(-30)(+80) fs, and an estimate for the lifetime of the second 2(+) state in C-16 have been obtained for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds of femtoseconds range by analyzing the Doppler-shifted gamma-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction O-18 (7.0 MeV/u) + Ta-181. The requested sensitivity could only be reached owing to the excellent performances of the Advanced gamma-Tracking Array AGATA, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two- and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for O-20 and with the no-core shell model for C-16. The present measurement shows the power of electromagnetic observables, determined with high-precision gamma spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetime measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense beams, produced by Isotope Separation On-Line (ISOL) techniques, become available. |
| Address |
[Ciemala, M.; Fornal, B.; Maj, A.; Bednarczyk, P.; Cieplicka-Orynczak, N.; Grebosz, J.; Iskra, L. W.; Kmiecik, M.; Mazurek, K.; Matejska-Minda, M.; Wasilewska, B.; Zieblinski, M.] Inst Nucl Phys, PAN, PL-31342 Krakow, Poland, Email: michal.ciemala@ifj.edu.pl; |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
|
Medium |
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| Area |
|
Expedition |
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Conference |
|
| Notes |
WOS:000517222700001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4311 |
| Permanent link to this record |
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| Author |
AGATA Collaboration (Clement, E. et al); Domingo-Pardo, C.; Gadea, A.; Perez-Vidal, R.M.; Civera, J.V. |
| Title |
Conceptual design of the AGATA 1 pi array at GANIL |
Type |
Journal Article |
| Year |
2017 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
| Volume |
855 |
Issue |
|
Pages |
1-12 |
| Keywords |
AGATA spectrometer; GANIL facility; gamma-ray tracking; Pulse shape analysis; VAMOS plus plus spectrometer; NEDA detector; DIAMANT detector; PARIS LaBr3 detector; FATIMA LaBr3 detector; Plunger device |
| Abstract |
The Advanced GAmma Tracking Array (AGATA) has been installed at the GANIL facility, Caen-France. This setup exploits the stable and radioactive heavy-ions beams delivered by the cyclotron accelerator complex of GANIL. Additionally, it benefits from a large palette of ancillary detectors and spectrometers to address in-beam gamma-ray spectroscopy of exotic nuclei. The set-up has been designed to couple AGATA with a magnetic spectrometer, charged-particle and neutron detectors, scintillators for the detection of high-energy gamma rays and other devices such as a plunger to measure nuclear lifetimes. In this paper, the design and the mechanical characteristics of the set-up are described. Based on simulations, expected performances of the AGATA l pi array are presented. |
| Address |
[Clement, E.; Michelagnoli, C.; de France, G.; Li, H. J.; Lemasson, A.; Dejeon, C. Barthe; Beuzard, M.; Bougault, P.; Cacitti, J.; Foucher, J. -L.; Fremont, G.; Gangnant, P.; Goupil, J.; Houarner, C.; Jean, M.; Lefevre, A.; Legeard, L.; Legruel, F.; Maugeais, C.; Menager, L.; Menard, N.; Munoz, H.; Ozille, M.; Raine, B.; Ropert, J. A.; Saillant, F.; Spitaels, C.; Tripon, M.; Vallerand, Ph.; Voltolini, G.; Lopez-Martens, A.] CEA, DRF, CNRS, IN2P3,GANIL, F-14076 Caen 05, France |
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| Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0168-9002 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000399846900001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3091 |
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| Author |
Delafosse, C. et al; Gadea, A.; Perez-Vidal, R.M.; Domingo-Pardo, C. |
| Title |
Pseudospin Symmetry and Microscopic Origin of Shape Coexistence in the Ni-78 Region: A Hint from Lifetime Measurements |
Type |
Journal Article |
| Year |
2018 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
121 |
Issue |
19 |
Pages |
192502 - 7pp |
| Keywords |
|
| Abstract |
Lifetime measurements of excited states of the light N = 52 isotones Kr-88, Se-86, and Ge-84 have been performed, using the recoil distance Doppler shift method and VAMOS and AGATA spectrometers for particle identification and gamma spectroscopy, respectively. The reduced electric quadrupole transition probabilities B(E2; 2(+)-> 0(+)) and B(E2; 4(+)-> 2(+)) were obtained for the first time for the hard-to-reach 84Ge. While the B(E2; 2(+)-> 0(+) ) values of Kr-88, Se-86 saturate the maximum quadrupole collectivity offered by the natural valence (3s, 2d, 1g(7/2), 1h(11/2)) space of an inert Ni-78 core, the value obtained for Ge-84 largely exceeds it, suggesting that shape coexistence phenomena, previously reported at N less than or similar to 49, extend beyond N = 50. The onset of collectivity at Z = 32 is understood as due to a pseudo-SU(3) organization of the proton single-particle sequence reflecting a clear manifestation of pseudospin symmetry. It is realized that the latter provides actually reliable guidance for understanding the observed proton and neutron single particle structure in the whole medium-mass region, from Ni to Sn, pointing towards the important role of the isovector-vector rho field in shell-structure evolution. |
| Address |
[Delafosse, C.; Verney, D.; Marevic, P.; Gottardo, A.; Babo, M.; Franchoo, S.; Ibrahim, F.; Matea, I; Olivier, L.; Portail, C.; Stefan, I] Univ Paris Saclay, Univ Paris Sud, CNRS IN2P3, Inst Phys Nucl, F-91406 Orsay, France, Email: verney@ipno.in2p3.fr |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-9007 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000449791600008 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3800 |
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| Author |
Dudouet, J. et al; Gadea, A.; Perez-Vidal, R.M. |
| Title |
Excitations of the magic N=50 neutron-core revealed in Ga-81 |
Type |
Journal Article |
| Year |
2019 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
100 |
Issue |
1 |
Pages |
011301 - 6pp |
| Keywords |
|
| Abstract |
The high-spin states of the neutron-rich Ga-81, with three valence protons outside a Ni-78 core, were measured. The measurement involved prompt gamma-ray spectroscopy of fission fragments isotopically identified using the combination of the variable mode spectrometer (VAMOS++) and the advanced gamma tracking array (AGATA). The new gamma-ray transitions, observed in coincidence with Ga-81 ions, and the corresponding level scheme do not confirm the high-spin levels reported earlier. The newly observed high-spin states in Ga-81 are interpreted using the results of state-of-the-art large-scale shell model (LSSM) calculations. The lower excitation energy levels are understood as resulting from the recoupling of three valence protons to the closed doubly magic core, while the highest excitation energy levels correspond to excitations of the magic N = 50 neutron core. These results support the doubly magic character of Ni-78 and the persistence of the N = 50 shell closure but also highlight the presence of strong proton-neutron correlations associated with the promotion of neutrons across the magic N = 50 shell gap, only few nucleons away from Ni-78. |
| Address |
[Dudouet, J.; Maquart, G.; Stezowski, O.; Ducoin, C.; Guinet, D.; Redon, N.] Univ Lyon 1, CNRS IN2P3, IPN Lyon, F-69622 Villeurbanne, France, Email: jeremie.dudouet@csnsm.in2p3.fr |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000475500200001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4095 |
| Permanent link to this record |
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| Author |
Dudouet, J. et al; Domingo-Pardo, C.; Gadea, A.; Perez-Vidal, R.M. |
| Title |
Kr-96(36)60-Low-Z Boundary of the Island of Deformation at N=60 |
Type |
Journal Article |
| Year |
2017 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
118 |
Issue |
16 |
Pages |
162501 - 6pp |
| Keywords |
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| Abstract |
Prompt.-ray spectroscopy of the neutron-rich Kr-96, produced in transfer-and fusion-induced fission reactions, has been performed using the combination of the Advanced Gamma Tracking Array and the VAMOS + +spectrometer. A second excited state, assigned to J pi = 4(+), is observed for the first time, and a previously reported level energy of the first 2+ excited state is confirmed. The measured energy ratio R-4/2 = E(4(+))/E(2(+)) = 2.12(1) indicates that this nucleus does not show a well-developed collectivity contrary to that seen in heavier N = 60 isotones. This new measurement highlights an abrupt transition of the degree of collectivity as a function of the proton number at Z = 36, of similar amplitude to that observed at N = 60 at higher Z values. A possible reason for this abrupt transition could be related to the insufficient proton excitations in the g(9/2), d(5/2), and s(1/2) orbitals to generate strong quadrupole correlations or to the coexistence of competing different shapes. An unexpected continuous decrease of R-4/2 as a function of the neutron number up to N = 60 is also evidenced. This measurement establishes the Kr isotopic chain as the low-Z boundary of the island of deformation for N = 60 isotones. A comparison with available theoretical predictions using different beyond mean-field approaches shows that these models fail to reproduce the abrupt transitions at N = 60 and Z = 36. |
| Address |
[Dudouet, J.; Maquart, G.; Stezowski, O.; Redon, N.] Univ Lyon 1, CNRS IN2P3, IPN Lyon, F-69622 Villeurbanne, France, Email: j.dudouet@ipnl.in2p3.fr |
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| Publisher |
Amer Physical Soc |
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| Language |
English |
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| ISSN |
0031-9007 |
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| Notes |
WOS:000399816500006 |
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no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3098 |
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