| Records |
| Author |
Wimmer, K. et al; Algora, A.; Rubio, B. |
| Title |
Shape Changes in the Mirror Nuclei Kr-70 and Se-70 |
Type |
Journal Article |
| Year |
2021 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
126 |
Issue |
7 |
Pages |
072501 - 6pp |
| Keywords |
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| Abstract |
We studied the proton-rich T-z = -1 nucleus Kr-70 through inelastic scattering at intermediate energies in order to extract the reduced transition probability, B(E2; 0+ -> 2+). Comparison with the other members of the A = 70 isospin triplet, Br-70 and Se-70, studied in the same experiment, shows a 3 sigma deviation from the expected linearity of the electromagnetic matrix elements as a function of T-z. At present, no established nuclear structure theory can describe this observed deviation quantitatively. This is the first violation of isospin symmetry at this level observed in the transition matrix elements. A heuristic approach may explain the anomaly by a shape change between the mirror nuclei Kr-70 and Se-70 contrary to the model predictions. |
| Address |
[Wimmer, K.] CSIC, Inst Estruct Mat, E-28006 Madrid, Spain, Email: k.wimmer@csic.es |
| 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 |
0031-9007 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000619237200006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4715 |
| Permanent link to this record |
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| Author |
Wimmer, K. et al; Algora, A.; Rubio, B. |
| Title |
Discovery of Br-68 in secondary reactions of radioactive beams |
Type |
Journal Article |
| Year |
2019 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
795 |
Issue |
|
Pages |
266-270 |
| Keywords |
Radioactive beams; New isotope; Direct reaction |
| Abstract |
The proton-rich isotope Br-68 was discovered in secondary fragmentation reactions of fast radioactive beams. Proton-rich secondary beams of (70,71,72) Kr and Br-70, produced at the RIKEN Nishina Center and identified by the BigRIPS fragment separator, impinged on a secondary Be-9 target. Unambiguous particle identification behind the secondary target was achieved with the ZeroDegree spectrometer. Based on the expected direct production cross sections from neighboring isotopes, the lifetime of the ground or long-lived isomeric state of Br-68 was estimated. The results suggest that secondary fragmentation reactions, where relatively few nucleons are removed from the projectile, offer an alternative way to search for new isotopes, as these reactions populate preferentially low-lying states. |
| Address |
[Wimmer, K.; Ando, T.; Koyama, S.; Nagamine, S.; Niikura, M.; Saito, Ty; Sakurai, H.; Taniuchi, R.] Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan, Email: wimmer@phys.s.u-tokyo.ac.jp |
| Corporate Author |
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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 |
|
Expedition |
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Conference |
|
| Notes |
WOS:000477924000037 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4100 |
| Permanent link to this record |
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| Author |
Wimmer, K. et al: Huyuk, T. |
| Title |
Isospin symmetry in the T=1, A=62 triplet |
Type |
Journal Article |
| Year |
2023 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
847 |
Issue |
|
Pages |
138249 - 7pp |
| Keywords |
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| Abstract |
Excited states in the Tz = 0, -1 nuclei Ga-62 and Ge-62 were populated in direct reactions of relativistic radioactive ion beams at the RIBF. Coincident gamma rays were measured with the DALI2(+) array and uniquely assigned to the A = 62 isobars. In addition, Ge-62 was also studied independently at JYFL-ACCLAB using the Mg-24(Ca-40,2n)Ge-62 fusion-evaporation reaction. The first excited T = 1, J(pi) = 2(+) states in Ga-62 and Ge-62 were identified at 979(1) and 965(1) keV, respectively, resolving discrepant interpretations in the literature. States beyond the first 2+ state in Ge-62 were also identified for the first time in the present work. The results are compared with shell-model calculations in the f p. model space. Mirror and triplet energy differences are analyzed in terms of individual charge-symmetry and charge-independence breaking contributions. The MED results confirm the shrinkage of the p-orbits' radii when they are occupied by at least one nucleon on average. |
| Address |
[Wimmer, K.; Arici, T.; Ge, Z.] GSI Helmholtzzentrum Schwerionenforsch, D-64291 Darmstadt, Germany, Email: k.wimmer@gsi.de |
| Corporate Author |
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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 |
|
Expedition |
|
Conference |
|
| Notes |
WOS:001111929500001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5834 |
| Permanent link to this record |
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| |
| Author |
Wimmer, K. et al; Huyuk, T. |
| Title |
Precision tests of isospin symmetry through Coulomb excitation of A=62 nuclei |
Type |
Journal Article |
| Year |
2026 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
876 |
Issue |
|
Pages |
140391 - 6pp |
| Keywords |
Rare isotope beams; Electromagnetic transition probabilities; Coulomb excitation; Isospin symmetry |
| Abstract |
Isospin symmetry in the A = 62 mass system was investigated through Coulomb excitation reactions at the RIKEN Radioactive Isotope Beam Factory. Beams of 62Zn, 62Ga, and 62Ge were studied using the BigRIPS-ZeroDegree-DALI2+ setup under identical experimental conditions, allowing for cancellation of systematic uncertainties. Inelastic scattering cross sections measured with two different targets were used to extract nuclear deformation lengths and E2 matrix elements. The isospin symmetry of the A = 62 system was rigorously tested by examining the linearity of the proton matrix elements within the triplet with high precision. The observed linear relationship between the reduced proton matrix elements for the three nuclei holds within experimental uncertainties, providing a stringent test of isospin symmetry. This experiment provides the most accurate test, to date, of isospin symmetry rules using transition matrix elements. These results were interpreted using large-scale shell-model calculations, offering valuable insights into isospin symmetry behavior in this region of the nuclear chart. |
| Address |
[Wimmer, K.; Arici, T.] GSI Helmholtzzentrum Schwer Forsch, D-64291 Darmstadt, Germany; [Wimmer, K.; Koiwai, T.; Niikura, M.; Taniuchi, R.] Univ Tokyo, Dept Phys, Bunkyo Ku, Hongo, Tokyo 1130033, Japan; [Wimmer, K.; Browne, F.; Doornenbal, P.; Koiwai, T.; Mauss, B.; Taniuchi, R.] RIKEN, Nishina Ctr, 2-1 Hirosawa, Wako, Saitama 3510198, Japan; [Huyuk, T.] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46071 Valencia, Spain; [Lenzi, S. M.; Recchia, F.] Univ Padua, Dipartimento Fis & Astron, I-35131 Padua, Italy; [Lenzi, S. M.; Cortes, M. L.; Napoli, D.; Recchia, F.] INFN, Sez Padova, I-35131 Padua, Italy; [Poves, A.] Univ Autonoma Madrid, Dept Fis Teor, Madrid 28049, Spain; [Bentley, M. A.; Pereira-Lopez, X.; Uthayakumaar, S.; Wadsworth, R.] Univ York, Sch Phys Engn & Technol, York YO10 5DD, England; [Furumoto, T.] Yokohama Natl Univ, Coll Educ, Yokohama 2408501, Japan; [Imai, N.; Kitamura, N.] Univ Tokyo, Ctr Nucl Study, Bunkyo Ku, Tokyo 1130033, Japan; [Jungclaus, A.; Vaquero, V.] CSIC, Inst Estruct Mat, E-28006 Madrid, Spain; [Longfellow, B.] Michigan State Univ, Dept Phys & Astron, Cyclotron Lab, Natl Superconducting, E Lansing, MI 48824 USA; [Lozeva, R.] Univ Paris Saclay, IJCLab, IN2P3, CNRS, F-91405 Orsay, France; [Ruotsalainen, P.] Univ Jyvaskyla, Dept Phys, Accelerator Lab, FI-40014 Jyvaskyla, Finland; [Yajzey, R.] Jazan Univ, Coll Sci, Dept Phys Sci, Phys Div, POB 114, Jazan 45142, Saudi Arabia, Email: k.wimmer@gsi.de |
| Corporate Author |
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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 |
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| Notes |
WOS:001744071000001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
7184 |
| Permanent link to this record |
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| Author |
Wimmer, K. et al; Algora, A.; Rubio, B. |
| Title |
Shape coexistence and isospin symmetry in A=70 nuclei: Spectroscopy of the T-z =-1 nucleus Kr-70 |
Type |
Journal Article |
| Year |
2018 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
785 |
Issue |
|
Pages |
441-446 |
| Keywords |
Radioactive beams; Gamma-ray spectroscopy; Mirror symmetry; Shape coexistence |
| Abstract |
Excited states in the T-z = -1 nucleus Kr-70 have been populated using inelastic scattering of a radioactive Kr-70 beam as well as one- and two-neutron removal reactions from Kr-71,Kr-72 at intermediate beam energies. The level scheme of Kr-70 was constructed from the observed gamma-ray transitions and coincidences. Tentative spin and parity assignments were made based on comparison with the mirror nucleus Se-70. Asecond 2(+) state and a candidate for the corresponding 4(2)(+) state suggest shape coexistence in Kr-70. |
| Address |
[Wimmer, K.; Ando, T.; Koyama, S.; Nagamine, S.; Niikura, M.; Saito, T. Y.; Sakurai, H.; Taniuchi, R.] Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan, Email: wimmer@phys.s.u-tokyo.ac.jp |
| Corporate Author |
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Thesis |
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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 |
0370-2693 |
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:000447424000064 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3795 |
| Permanent link to this record |
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| Author |
Wimmer, K. et al; Algora, A.; Rubio, B. |
| Title |
Shape coexistence revealed in the N = Z isotope Kr-72 through inelastic scattering |
Type |
Journal Article |
| Year |
2020 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
| Volume |
56 |
Issue |
6 |
Pages |
159 - 12pp |
| Keywords |
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| Abstract |
The N = Z = 36 nucleus Kr-72 has been studied by inelastic scattering at intermediate energies. Two targets, Be-9 and Au-197, were used to extract the nuclear deformation length, delta(N), and the reduced E2 transition probability, B(E2). The previously unknown non-yrast 2(+) and 4(+) states as well as a new candidate for the octupole 3(-) state have been observed in the scattering on the Be target and placed in the level scheme based on gamma – gamma coincidences. The second 2(+) state was also observed in the scattering on the Au target and the B(E2; 2(2)(+) -> 0(1)(+)) value could be determined for the first time. Analyzing the results in terms of a two-band mixing model shows clear evidence for a oblate-prolate shape coexistence and can be explained by a shape change from an oblate ground state to prolate deformed yrast band from the first 2+ state. This interpretation is corroborated by beyond mean field calculations using the Gogny D1S interaction. |
| Address |
[Wimmer, K.; Ando, T.; Koyama, S.; Nagamine, S.; Niikura, M.; Saito, T. Y.; Sakurai, H.; Taniuchi, R.] Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan, Email: k.wimmer@csic.es |
| Corporate Author |
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Thesis |
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| Publisher |
Springer |
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 |
1434-6001 |
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:000540063900002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4428 |
| Permanent link to this record |
