| Records |
| Author |
Guadilla, V. et al; Algora, A.; Tain, J.L.; Agramunt, J.; Jordan, D.; Monserrate, M.; Montaner-Piza, A.; Nacher, E.; Orrigo, S.E.A.; Rubio, B.; Valencia, E. |
| Title |
Total absorption gamma-ray spectroscopy of the ss decays of Y-96gs,Y-m |
Type |
Journal Article |
| Year |
2022 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
106 |
Issue |
1 |
Pages  |
014306 - 14pp |
| Keywords |
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| Abstract |
The ss decays of the ground state (gs) and isomeric state (m) of Y-96 have been studied with the total absorption gamma-ray spectroscopy technique at the Ion Guide Isotope Separator On-Line facility. The separation of the 8(+) isomeric state from the 0(-) ground state was achieved thanks to the purification capabilities of the JYFLTRAP double Penning trap system. The ss-intensity distributions of both decays have been independently determined. In the analyses the deexcitation of the 1581.6 keV level in Zr-96, in which conversion electron emission competes with pair production, has been carefully considered and found to have significant impact on the ss-detector efficiency, influencing the ss-intensity distribution obtained. Our results for Y-96gs (0(-)) confirm the large ground state to ground state ss-intensity probability, although a slightly larger value than reported in previous studies was obtained, amounting to 96.6(-2.1)(+0.3) % of the total ss intensity. Given that the decay of Y-96gs is the second most important contributor to the reactor antineutrino spectrum between 5 and 7 MeV, the impact of the present results on reactor antineutrino summation calculations has been evaluated. In the decay of Y-96m (8(+)), previously undetected ss intensity in transitions to states above 6 MeV has been observed. This shows the importance of total absorption gamma-ray spectroscopy measurements of ss decays with highly fragmented deexcitation patterns. Y-96m (8(+)) is a major contributor to reactor decay heat in uranium-plutonium and thorium-uranium fuels around 10 s after fission pulses, and the newly measured average ss and gamma energies differ significantly from the previous values in evaluated databases. The discrepancy is far above the previously quoted uncertainties. Finally, we also report on the successful implementation of an innovative total absorption gamma-ray spectroscopy analysis of the module-multiplicity gated spectra, as a first proof of principle to distinguish between decaying states with very different spin-parity values. |
| Address |
[Guadilla, V; Le Meur, L.; Fallot, M.; Briz, J. A.; Estienne, M.; Giot, L.; Porta, A.; Cucoanes, A.; Shiba, T.; Zakari-Issoufou, A-A] Univ Nantes, Subatech, IMT Atlantique, CNRS IN2P3, F-44307 Nantes, France, Email: vguadilla@fuw.edu.pl |
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| Publisher |
Amer Physical Soc |
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English |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
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Expedition |
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Conference |
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| Notes |
WOS:000832364800001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5313 |
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| Author |
Fujita, Y. et al; Algora, A.; Estevez-Aguado, E.; Molina, F.; Rubio, B. |
| Title |
High-resolution study of T-z =+2 ->+1 Gamow-Teller transitions in the Ca-44(3He,t)Sc-44 reaction |
Type |
Journal Article |
| Year |
2013 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
88 |
Issue |
1 |
Pages |
014308 - 18pp |
| Keywords |
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| Abstract |
In order to study the Gamow-Teller (GT) transitions from the T-z = +2 nucleus Ca-44 to the T-z = +1 nucleus Sc-44, where T-z is the z component of isospin T, we performed the (p, n)-type (He-3, t) charge-exchange (CE) reaction at 140 MeV/nucleon and the scattering angles 0 degrees and 2.5 degrees. An energy resolution of 28 keV, that was realized by applying matching techniques to the magnetic spectrometer system, allowed the study of fragmented states. The GT transition strengths, B(GT), were derived up to the excitation energy (E-x) of 13.7 MeV assuming the proportionality between cross sections and B(GT) values. The total sum of B(GT) values in discrete states was 3.7, which was 31% of the sum-rule-limit value of 12. Shell model calculations using the GXPF1J interaction could reproduce the gross features of the experimental B(GT) distribution, but not the fragmentation of the strength. By introducing the concepts of isospin, properties of isospin analogous transitions and states were investigated. (i) Assuming isospin symmetry, the T-z = +2 -> +1 and T-z = -2 -> -1 mirror GT transitions should have the same properties, where the latter can be studied in the beta decay of Cr-44 to V-44. First, we confirmed that the beta-decay half-life T-1/2 of Cr-44 can be reproduced using the B(GT) distribution from the Ca-44(He-3, t) measurement. Then, the 0 degrees, (3He, t) spectrum was modified to deduce the “beta-decay spectrum” and it was compared with the delayed-proton spectrum from the Cr-44 beta decay. The two spectra were mostly in agreement for the GT excitations, but suppression of the proton decay was found for the T = 2 isobaric analog state (IAS). (ii) Starting from the T = 2 ground state of 44Ca, the (3He, t) can excite GT states (state populated by GT transitions) with T = 1, 2, and 3. On the other hand, the Ca-44(p, p') reaction can excite spin-M1 states (states populated by spin-M1 transitions) with T = 2 and 3 that are analogous to the T = 2 and 3 GT states, respectively. By comparing the spectra from these two reactions, a T value of 2 is suggested for several GT states in the E-x = 11.5-13.7 MeV region. (iii) It has been suggested that the T = 2, J(pi) = 0(+) double isobaric analog state (DIAS) at 9.338 MeV in the T-z = 0 nucleus Ti-44 forms an isospin-mixed doublet with a subsidiary 0(+) state at 9.298 MeV. Since no corresponding state was found in the T-z = +1 nucleus Sc-44, we suggest T = 0 for the subsidiary state. |
| Address |
[Fujita, Y.; Fujita, H.] Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043, Japan, Email: fujita@rcnp.osaka-u.ac.jp |
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Amer Physical Soc |
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English |
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Series Issue |
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Edition |
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| ISSN |
0556-2813 |
ISBN |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000321839100001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1495 |
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| Author |
Nacher, E.; Rubio, B.; Algora, A.; Cano-Ott, D.; Tain, J.L.; Gadea, A.; Agramunt, J.; Gierlik, M.; Karny, M.; Janas, Z.; Roeckl, E.; Blazhev, A.; Collatz, R.; Doring, J.; Hellstrom, M.; Hu, Z.; Kirchner, R.; Mukha, I.; Plettner, C.; Shibata, M.; Rykaczewski, K.; Batist, L.; Moroz, F.; Wittmann, V.; Valiente-Dobon, J.J. |
| Title |
Observations of the Gamow-Teller resonance in the rare-earth nuclei above Gd-146 populated in beta decay |
Type |
Journal Article |
| Year |
2016 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
93 |
Issue |
1 |
Pages |
014308 - 13pp |
| Keywords |
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| Abstract |
The rare-earth region of the nuclear table around the quasi-doubly magic nucleus Gd-146 is one of the very few places in which the Gamow-Teller (GT) resonance can be populated in beta decay. The appropriate technique to study such a phenomenon is total absorption spectroscopy, thanks to which one can measure the B(GT) distribution in beta-decay experiments even when it is very fragmented and lies at high excitation energy in the daughter nucleus. Results on the GT resonance measured in the beta decay of the odd-Z, N = 83 nuclei Tb-148, Ho-150, and Tm-152 are presented in this work and compared with shell-model calculations. The tail of the resonance is clearly observed up to the limit imposed by the Q value. This observation is important in the context of the understanding of the “quenching” of the GT strength. |
| Address |
[Nacher, E.; Rubio, B.; Algora, A.; Cano-Ott, D.; Tain, J. L.; Gadea, A.; Agramunt, J.] Univ Valencia, CSIC, IFIC, Valencia 46071, Spain, Email: berta.rubio@ific.uv.es |
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Amer Physical Soc |
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English |
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Series Issue |
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Edition |
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| ISSN |
0556-2813 |
ISBN |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000368298200001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2522 |
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| Author |
IDS Collaboration (Stryjczyk, M. et al.); Nacher, E. |
| Title |
Simultaneous gamma-ray and electron spectroscopy of 182,184,186Hg isotopes |
Type |
Journal Article |
| Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
108 |
Issue |
1 |
Pages |
014308 - 20pp |
| Keywords |
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| Abstract |
Background: The mercury isotopes around N = 104 are a well-known example of nuclei exhibiting shape coex-istence. Mixing of configurations can be studied by measuring the monopole strength rho^2(E0), however, currently the experimental information is scarce and lacks precision, especially for the I^pi -> I^pi (I not = 0) transitions. Purpose: The goals of this study were to increase the precision of the known branching ratios and internal conversion coefficients, to increase the amount of available information regarding excited states in 182,184,186Hg, and to interpret the results in the framework of shape coexistence using different models. Method: The low-energy structures in 182,184,186Hg were populated in the & beta; decay of 182,184,186Tl, produced at ISOLDE, CERN and purified by laser ionization and mass separation. The & gamma;-ray and internal conversion electron events were detected by five germanium clover detectors and a segmented silicon detector, respectively, and correlated in time to build decay schemes.Results: In total, 193, 178, and 156 transitions, including 144, 140, and 108 observed for the first time in a & beta;-decay experiment, were assigned to 182,184,186Hg, respectively. Internal conversion coefficients were determined for 23 transitions, out of which 12 had an E0 component. Extracted branching ratios allowed the sign of the interference term in 182Hg as well as & rho;2(E 0; 0+2 & RARR; 0+1 ) and B(E2; 0+2 & RARR; 2+1 ) in 184Hg to be determined. By means of electron-electron coincidences, the 0+3 state was identified in 184Hg. The experimental results were qualitatively reproduced by five theoretical approaches, the interacting boson model with configuration mixing with two different parametrizations, the general Bohr Hamiltonian, the beyond mean-field model, and the symmetry-conserving configuration-mixing model. However, a quantitative description is lacking. Conclusions: The presence of shape coexistence in neutron-deficient mercury isotopes was confirmed and evidence for the phenomenon existing at higher energies was found. The new experimental results provide important spectroscopic input for future Coulomb excitation studies. |
| Address |
[Stryjczyk, M.; Andel, B.; Rezynkina, K.; Van Duppen, P.; De Witte, H.; Huyse, M.] Katholieke Univ Leuven, Inst Kern Stralingsfys, Celestijnenlaan 200D, B-3001 Leuven, Belgium, Email: marek.m.stryjczyk@jyu.fi |
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Amer Physical Soc |
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English |
Summary Language |
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Series Title |
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Abbreviated Series Title |
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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:001054768200002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5630 |
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| Author |
AGATA Collaboration (Kaya, L. et al); Gadea, A. |
| Title |
High-spin structure in the transitional nucleus Xe-131: Competitive neutron and proton alignment in the vicinity of the N=82 shell closure |
Type |
Journal Article |
| Year |
2018 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
98 |
Issue |
1 |
Pages |
014309 - 19pp |
| Keywords |
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| Abstract |
The transitional nucleus Xe-131 is investigated after multinucleon transfer in the Xe-136 + Pb-208 and Xe-136 +U-238 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 Sn-124(B-11) ,p3n)Xe-131 employing the High-efficiency Observatory for gamma-Ray Unique Spectroscopy (HORUS) gamma-ray array coupled to a double-sided silicon strip detector at the University of Cologne, Germany. The level scheme of Xe-131 is extended to 5 MeV. A pronounced backbending is observed at (h) over bar omega approximate to 0.4 MeV along the negative-parity one-quasiparticle vh(11/12)(alpha = -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 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 Xe129-132 provide insight into the changing nuclear structure along the Xe chain towards the N = 82 shell closure. Proton occupancy in the pi 0h(11/2) orbital is found to be decisive for the description of the observed backbending phenomenon. |
| Address |
[Kaya, L.; Vogt, A.; Reiter, P.; Birkenbach, B.; Blazhev, A.; Arnswald, K.; Eberth, J.; Fransen, C.; Fu, B.; Hess, H.; Hetzenegger, R.; Hirsch, R.; Jolie, J.; Lewandowski, L.; Mueller-Gatermann, C.; Queiser, M.; Rosiak, D.; Saed-Samii, N.; Schneiders, D.; Seidlitz, M.; Siebeck, B.; Steinbach, T.; Wolf, K.; Zell, K. O.] Univ Cologne, Inst Kernphys, D-50937 Cologne, Germany, Email: levent.kaya@ikp.uni-koeln.de |
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| Publisher |
Amer Physical Soc |
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English |
Summary Language |
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Series Title |
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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:000437737600001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3650 |
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| Author |
Aydin, S. et al; Gadea, A.; Huyuk, T. |
| Title |
High-spin level structure of S-35 |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
89 |
Issue |
1 |
Pages |
014310 - 9pp |
| Keywords |
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| Abstract |
The nucleus S-35 has been studied by in-beam gamma-ray spectroscopy using the Mg-24(N-14,3p) fusion-evaporation reaction at E-lab = 40 MeV. A level scheme extended up to J(pi) = 17/2(+) at 8023 keV and J(pi) = 13/2(-) at 6352 keV has been established. Lifetimes of six excited states have been determined by applying the Doppler shift attenuation method. The experimental data have been compared with the results of large-scale shell model calculations performed using different effective interactions and model spaces allowing particle-hole excitations across the N = Z = 20 shell gap. |
| Address |
[Aydin, S.] Univ Aksaray, Dept Phys, Aksaray, Turkey |
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| Publisher |
Amer Physical Soc |
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English |
Summary Language |
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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 |
0556-2813 |
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:000332152100004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1723 |
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| Author |
Wasilewska, B. et al; Gaudilla, V. |
| Title |
gamma decay to the ground state from the excitations above the neutron threshold in the Pb-208(p, p ' gamma) reaction at 85 MeV |
Type |
Journal Article |
| Year |
2022 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
105 |
Issue |
1 |
Pages |
014310 - 7pp |
| Keywords |
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| Abstract |
A new measurement of gamma decay from the states above the neutron threshold in Pb-208 has been performed at Cyclotron Centre Bronowice in Krakow, Poland. The main goal of the experiment was to observe the gamma decay to the ground state from the isoscalar giant quadrupole resonance (ISGQR). To this day, the only published observation of this phenomenon dates back to the late 1980s, where gamma decay to the ground state branching ratio was reported. At variance with the existing measurement using inelastic scattering of O-17, here proton inelastic scattering is employed. In particular, data were obtained for Pb-208(p, p'gamma) at 85 MeV beam energy, where gamma rays were measured for proton scattering angles 8.9 degrees, 10.7 degrees, 12.5 degrees, and 14.3 degrees. By applying a similar analysis method as in the previous experiment, the branching ratio of ISGQR gamma decay to the ground state was extracted from the data. |
| Address |
[Wasilewska, B.; Kmiecik, M.; Ciemala, M.; Maj, A.; Bednarczyk, P.; Ciepal, I; Fornal, B.; Grebosz, J.; Krzysiek, M.; Lasko, P.; Matejska-Minda, M.; Mazurek, K.; Parol, W.; Pawlowski, P.; Sowicki, B.; Zieblinski, M.; Cieplicka-Orynczak, N.; Iskra, L. W.; Jezabek, M.; Lukasik, J.] Polish Acad Sci, Inst Nucl Phys, PL-31342 Krakow, Poland, Email: Maria.Kmiecik@ifj.edu.pl |
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Amer Physical Soc |
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English |
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Abbreviated Series Title |
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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:000752560800007 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5127 |
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| Author |
Xu, Z.Y. et al; Algora, A.; Morales, A.I. |
| Title |
Beta-delayed neutron spectroscopy of 133In |
Type |
Journal Article |
| Year |
2023 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
108 |
Issue |
1 |
Pages |
014314 - 9pp |
| Keywords |
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| Abstract |
The decay properties of 133In were studied in detail at the ISOLDE Decay Station. The implementation of the Resonance Ionization Laser Ion Source allowed separate measurements of its 9/2+ ground state (133gIn) and 1/2- isomer (133mIn). With the use of & beta;-delayed neutron and & gamma; spectroscopy, the decay strengths above the neutron separation energy were quantified in this neutron-rich nucleus for the first time. The allowed Gamow-Teller transition 9/2+ & RARR; 7/2+ was located at 5.93 MeV in the 133gIn decay with a log ft = 4.7(1). In addition, several neutron-unbound states were populated at lower excitation energies by the first-forbidden decays of 133g,mIn. We assigned spins and parities to those neutron-unbound states based on the & beta;-decay selection rules, the log ft values, and systematics. |
| Address |
[Xu, Z. Y.; Madurga, M.; Grzywacz, R.; King, T. T.; Halverson, C.; Heideman, J.; Singh, M.; Yokoyama, R.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA |
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Amer Physical Soc |
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English |
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Series Title |
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Abbreviated Series Title |
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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:001062056700002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5757 |
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| Author |
Hafner, G. et al; Algora, A. |
| Title |
First lifetime investigations of N > 82 iodine isotopes: The quest for collectivity |
Type |
Journal Article |
| Year |
2021 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
104 |
Issue |
1 |
Pages |
014316 - 18pp |
| Keywords |
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| Abstract |
We report on spectroscopic information and lifetime measurements in the neutron-rich I-135,I-137,I-139 isotopes. This is the first lifetime data on iodine isotopes beyond N = 82. Excited states were populated in fast neutron-induced fission of U-238 at the ALTO facility of IJCLab with the LICORNE neutron source and detected using the hybrid nu-ball spectrometer. The level schemes of the I-135,I-137,I-139 isotopes are revised in terms of excited states with up to maximum spin-parity of (33/2(+)), populated for the first time in fast neutron-induced fission. We provide first results on the lifetimes of the (9/2(1)(+)) and (13/2(1)(+)) states in I-137 and I-139, and the (17/2(1)(+)) state in 137I. In addition, we give upper lifetime limits for the (11/2(1)(+)) states in I135-139, the (15/2(1)(+)) state in I-137, the (17/2(1)(+)) state in I-139, and reexamine the (29/2(1)(+)) state in I-137. The isomeric data in I-13(5) are reinvestigated, such as the previously known (15/2(1)(+)) and (23/21) isomers with T-1/2 of 1.64(14) and 4.6(7) ns, respectively, as obtained in this work. The new spectroscopic information is compared to that from spontaneous or thermal-neutron induced fission and discussed in the context of large scale shell-model (LSSM) calculations for the region beyond Sn-132, indicating the behavior of collectivity for the three valence-proton iodine chain with N = 82, 84, 86. |
| Address |
[Haefner, G.; Lozeva, R.; Lebois, M.; Jovancevic, N.; Thisse, D.; Wilson, J. N.; Babo, M.; Chakma, R.; Delafosse, C.; Hauschild, K.; Ibrahim, F.; Nemer, J.; Popovitch, Y.; Qi, L.; Ralet, D.; Tocabens, G.; Verney, D.] Univ Paris Saclay, IJCLab, CNRS IN2P3, F-91405 Orsay, France, Email: radomira.lozeva@ijclab.in2p3.fr |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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| Language |
English |
Summary Language |
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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:000674546900001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4913 |
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| Author |
Siciliano, M. et al; Gadea, A. |
| Title |
Shape coexistence in neutron-deficient Hg-188 investigated via lifetime measurements |
Type |
Journal Article |
| Year |
2020 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
102 |
Issue |
1 |
Pages |
014318 - 16pp |
| Keywords |
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| Abstract |
Background: Shape coexistence in the Z approximate to 82 region has been established in mercury, lead, and polonium isotopes. For even-even mercury isotopes with 100 <= N <= 106 multiple fingerprints of this phenomenon are observed, which seems to be no longer present for N >= 110. According to a number of theoretical calculations, shape coexistence is predicted in the Hg-188 isotope. Purpose: The aim of this work was to measure lifetimes of excited states in Hg-188 to infer their collective properties, such as the deformation. Extending the investigation to higher-spin states, which are expected to be less affected by band-mixing effects, can provide additional information on the coexisting structures. Methods: The Hg-188 nucleus was populated using two different fusion-evaporation reactions with two targets, Gd-158 and Gd-160, and a beam of S-34 provided by the Tandem-ALPI accelerator complex at the Laboratori Nazionali di Legnaro. The channels of interest were selected using the information from the Neutron Wall array, while the gamma rays were detected using the GALILEO gamma-ray spectrometer. Lifetimes of excited states were determined using the recoil-distance Doppler-shift method, employing the dedicated GALILEO plunger device. Results: Lifetimes of the states up to spin 16 (h) over bar were measured and the corresponding reduced transition probabilities were calculated. Assuming two-band mixing and adopting, as done commonly, the rotational model, the mixing strengths and the deformation parameters of the unperturbed structures were obtained from the experimental results. In order to shed light on the nature of the observed configurations in the Hg-188 nucleus, the extracted transition strengths were compared with those resulting from state-of-the-art beyond-mean-field calculations using the symmetry-conserving configuration-mixing approach, limited to axial shapes, and the five-dimensional collective Hamiltonian, including the triaxial degree of freedom. Conclusions: The first lifetime measurement for states with spin >= 6 suggested the presence of an almost spherical structure above the 12(1)(+) isomer and allowed elucidating the structure of the intruder band. The comparison of the extracted B(E2) strengths with the two-band mixing model allowed the determination of the ground-state band deformation. Both beyond-mean-field calculations predict coexistence of a weakly deformed band with a strongly prolate-deformed one, characterized by elongation parameters similar to those obtained experimentally, but the calculated relative position of the bands and their mixing strongly differ. |
| Address |
[Siciliano, M.; Zanon, I; Cicerchia, M.; de Angelis, G.; Galtarossa, F.; Gozzelino, A.; Hadynska-Klek, K.; Jaworski, G.; Napoli, D. R.; Valiente-Dobon, J. J.] INFN, Lab Nazl Legnaro, I-35020 Legnaro, Italy, Email: marco.siciliano@lnl.infn.it |
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| Publisher |
Amer Physical Soc |
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| Language |
English |
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| ISSN |
0556-2813 |
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| Notes |
WOS:000551404600001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4471 |
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