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Zanon I, Clément E, Goasduff A, Menéndez J, Miyagi T, Assié M, Ciemała M, Flavigny F, Lemasson A, Matta A, Ramos D, Rejmund M, Achouri L, Ackermann D, Barrientos D, Beaumel D, Benzoni G, Boston AJ, Boston HC, Bottoni S, Bracco A, Brugnara D, de France G, de Sereville N, Delaunay F, Desesquelles P, Didierjean F, Domingo-Prato C, Dudouet J, Eberth J, Fernández D, Fougères C, Gadea A, Galtarossa F, Girard-Alcindor V, Gonzales V, Gottardo A, Hammache F, Harkness-Brennan LJ, Hess H, Judson DS, Jungclaus A, Kaşkaş A, Kim YH, Kuşoğlu A, Labiche M, Leblond S, Lenain C, Lenzi SM, Leoni S, Li H, Ljungvall J, Lois-Fuentes J, Lopez-Martens A, Maj A, Menegazzo R, Mengoni D, Michelagnoli C, Million B, Napoli DR, Nyberg J, Pasqualato G, Podolyak Z, Pullia A, Quintana B, Recchia F, Regueira-Castro D, Reiter P, Rezynkina K, Rojo JS, Salsac MD, Sanchis E, Şenyiğit M, Siciliano M, Sohler D, Stezowski O, Theisen C, Utepov A, Valiente-Dobón JJ, Verney D, Zielinska M. High-Precision Spectroscopy of ^{20}O Benchmarking Ab Initio Calculations in Light Nuclei. PHYSICAL REVIEW LETTERS 2023; 131:262501. [PMID: 38215380 DOI: 10.1103/physrevlett.131.262501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 09/18/2023] [Accepted: 11/21/2023] [Indexed: 01/14/2024]
Abstract
The excited states of unstable ^{20}O were investigated via γ-ray spectroscopy following the ^{19}O(d,p)^{20}O reaction at 8 AMeV. By exploiting the Doppler shift attenuation method, the lifetimes of the 2_{2}^{+} and 3_{1}^{+} states were firmly established. From the γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+} and 3_{1}^{+} states, the B(E2) and B(M1) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of γ-ray transition probabilities with the valence space in medium similarity renormalization group ab initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab initio approaches using chiral effective field theory forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab initio models.
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Adamczak A, Antognini A, Berger N, Cocolios TE, Deokar N, Düllmann CE, Eggenberger A, Eichler R, Heines M, Hess H, Indelicato P, Kirch K, Knecht A, Krauth JJ, Nuber J, Ouf A, Papa A, Pohl R, Rapisarda E, Reiter P, Ritjoho N, Roccia S, Seidlitz M, Severijns N, von Schoeler K, Skawran A, Vogiatzi SM, Warr N, Wauters F. Muonic atom spectroscopy with microgram target material. THE EUROPEAN PHYSICAL JOURNAL. A, HADRONS AND NUCLEI 2023; 59:15. [PMID: 36751673 PMCID: PMC9898421 DOI: 10.1140/epja/s10050-023-00930-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 01/25/2023] [Indexed: 06/18/2023]
Abstract
Muonic atom spectroscopy-the measurement of the x rays emitted during the formation process of a muonic atom-has a long standing history in probing the shape and size of nuclei. In fact, almost all stable elements have been subject to muonic atom spectroscopy measurements and the absolute charge radii extracted from these measurements typically offer the highest accuracy available. However, so far only targets of at least a few hundred milligram could be used as it required to stop a muon beam directly in the target to form the muonic atom. We have developed a new method relying on repeated transfer reactions taking place inside a 100 bar hydrogen gas cell with an admixture of 0.25% deuterium that allows us to drastically reduce the amount of target material needed while still offering an adequate efficiency. Detailed simulations of the transfer reactions match the measured data, suggesting good understanding of the processes taking place inside the gas mixture. As a proof of principle we demonstrate the method with a measurement of the 2p-1s muonic x rays from a 5 μ g gold target.
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Pérez-Vidal RM, Gadea A, Domingo-Pardo C, Gargano A, Valiente-Dobón JJ, Clément E, Lemasson A, Coraggio L, Siciliano M, Szilner S, Bast M, Braunroth T, Collado J, Corina A, Dewald A, Doncel M, Dudouet J, de France G, Fransen C, González V, Hüyük T, Jacquot B, John PR, Jungclaus A, Kim YH, Korichi A, Labiche M, Lenzi S, Li H, Ljungvall J, López-Martens A, Mengoni D, Michelagnoli C, Müller-Gatermann C, Napoli DR, Navin A, Quintana B, Ramos D, Rejmund M, Sanchis E, Simpson J, Stezowski O, Wilmsen D, Zielińska M, Boston AJ, Barrientos D, Bednarczyk P, Benzoni G, Birkenbach B, Boston HC, Bracco A, Cederwall B, Cullen DM, Didierjean F, Eberth J, Gottardo A, Goupil J, Harkness-Brennan LJ, Hess H, Judson DS, Kaşkaş A, Korten W, Leoni S, Menegazzo R, Million B, Nyberg J, Podolyak Z, Pullia A, Ralet D, Recchia F, Reiter P, Rezynkina K, Salsac MD, Şenyiğit M, Sohler D, Theisen C, Verney D. Evidence of Partial Seniority Conservation in the πg_{9/2} Shell for the N=50 Isotones. PHYSICAL REVIEW LETTERS 2022; 129:112501. [PMID: 36154392 DOI: 10.1103/physrevlett.129.112501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 02/08/2022] [Accepted: 07/29/2022] [Indexed: 06/16/2023]
Abstract
The reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood. The conclusion is that seniority is largely conserved in the first πg_{9/2} orbital.
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Butler PA, Gaffney LP, Spagnoletti P, Konki J, Scheck M, Smith JF, Abrahams K, Bowry M, Cederkäll J, Chupp T, de Angelis G, De Witte H, Garrett PE, Goldkuhle A, Henrich C, Illana A, Johnston K, Joss DT, Keatings JM, Kelly NA, Komorowska M, Kröll T, Lozano M, Singh BSN, O'Donnell D, Ojala J, Page RD, Pedersen LG, Raison C, Reiter P, Rodriguez JA, Rosiak D, Rothe S, Shneidman TM, Siebeck B, Seidlitz M, Sinclair J, Stryjczyk M, Van Duppen P, Vinals S, Virtanen V, Warr N, Wrzosek-Lipska K, Zielinska M. Publisher Correction: The observation of vibrating pear-shapes in radon nuclei. Nat Commun 2020; 11:5185. [PMID: 33037232 PMCID: PMC7547707 DOI: 10.1038/s41467-020-19081-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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Butler PA, Gaffney LP, Spagnoletti P, Konki J, Scheck M, Smith JF, Abrahams K, Bowry M, Cederkäll J, Chupp T, de Angelis G, De Witte H, Garrett PE, Goldkuhle A, Henrich C, Illana A, Johnston K, Joss DT, Keatings JM, Kelly NA, Komorowska M, Kröll T, Lozano M, Singh BSN, O'Donnell D, Ojala J, Page RD, Pedersen LG, Raison C, Reiter P, Rodriguez JA, Rosiak D, Rothe S, Shneidman TM, Siebeck B, Seidlitz M, Sinclair J, Stryjczyk M, Van Duppen P, Vinals S, Virtanen V, Warr N, Wrzosek-Lipska K, Zielinska M. Addendum: The observation of vibrating pear-shapes in radon nuclei. Nat Commun 2020; 11:3560. [PMID: 32661232 PMCID: PMC7359340 DOI: 10.1038/s41467-020-17309-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Cederwall B, Liu X, Aktas Ö, Ertoprak A, Zhang W, Qi C, Clément E, de France G, Ralet D, Gadea A, Goasduff A, Jaworski G, Kuti I, Nyakó BM, Nyberg J, Palacz M, Wadsworth R, Valiente-Dobón JJ, Al-Azri H, Ataç Nyberg A, Bäck T, de Angelis G, Doncel M, Dudouet J, Gottardo A, Jurado M, Ljungvall J, Mengoni D, Napoli DR, Petrache CM, Sohler D, Timár J, Barrientos D, Bednarczyk P, Benzoni G, Birkenbach B, Boston AJ, Boston HC, Burrows I, Charles L, Ciemala M, Crespi FCL, Cullen DM, Désesquelles P, Domingo-Pardo C, Eberth J, Erduran N, Ertürk S, González V, Goupil J, Hess H, Huyuk T, Jungclaus A, Korten W, Lemasson A, Leoni S, Maj A, Menegazzo R, Million B, Perez-Vidal RM, Podolyak Z, Pullia A, Recchia F, Reiter P, Saillant F, Salsac MD, Sanchis E, Simpson J, Stezowski O, Theisen C, Zielińska M. Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus ^{88}Ru. PHYSICAL REVIEW LETTERS 2020; 124:062501. [PMID: 32109090 DOI: 10.1103/physrevlett.124.062501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/27/2019] [Accepted: 12/18/2019] [Indexed: 06/10/2023]
Abstract
The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N=Z) nuclide _{44}^{88}Ru_{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 ^{88}Ru were populated via the ^{54}Fe(^{36}Ar,2nγ)^{88}Ru^{*} fusion-evaporation reaction at the Grand Accélérateur National d'Ions Lourds (GANIL) accelerator complex. The observed γ-ray cascade is assigned to ^{88}Ru using clean prompt γ-γ-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.
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Butler PA, Gaffney LP, Spagnoletti P, Abrahams K, Bowry M, Cederkäll J, de Angelis G, De Witte H, Garrett PE, Goldkuhle A, Henrich C, Illana A, Johnston K, Joss DT, Keatings JM, Kelly NA, Komorowska M, Konki J, Kröll T, Lozano M, Nara Singh BS, O'Donnell D, Ojala J, Page RD, Pedersen LG, Raison C, Reiter P, Rodriguez JA, Rosiak D, Rothe S, Scheck M, Seidlitz M, Shneidman TM, Siebeck B, Sinclair J, Smith JF, Stryjczyk M, Van Duppen P, Vinals S, Virtanen V, Warr N, Wrzosek-Lipska K, Zielińska M. Evolution of Octupole Deformation in Radium Nuclei from Coulomb Excitation of Radioactive ^{222}Ra and ^{228}Ra Beams. PHYSICAL REVIEW LETTERS 2020; 124:042503. [PMID: 32058764 DOI: 10.1103/physrevlett.124.042503] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Indexed: 06/10/2023]
Abstract
There is sparse direct experimental evidence that atomic nuclei can exhibit stable "pear" shapes arising from strong octupole correlations. In order to investigate the nature of octupole collectivity in radium isotopes, electric octupole (E3) matrix elements have been determined for transitions in ^{222,228}Ra nuclei using the method of sub-barrier, multistep Coulomb excitation. Beams of the radioactive radium isotopes were provided by the HIE-ISOLDE facility at CERN. The observed pattern of E3 matrix elements for different nuclear transitions is explained by describing ^{222}Ra as pear shaped with stable octupole deformation, while ^{228}Ra behaves like an octupole vibrator.
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Butler PA, Gaffney LP, Spagnoletti P, Konki J, Scheck M, Smith JF, Abrahams K, Bowry M, Cederkäll J, Chupp T, de Angelis G, De Witte H, Garrett PE, Goldkuhle A, Henrich C, Illana A, Johnston K, Joss DT, Keatings JM, Kelly NA, Komorowska M, Kröll T, Lozano M, Nara Singh BS, O'Donnell D, Ojala J, Page RD, Pedersen LG, Raison C, Reiter P, Rodriguez JA, Rosiak D, Rothe S, Shneidman TM, Siebeck B, Seidlitz M, Sinclair J, Stryjczyk M, Van Duppen P, Vinals S, Virtanen V, Warr N, Wrzosek-Lipska K, Zielinska M. The observation of vibrating pear-shapes in radon nuclei. Nat Commun 2019; 10:2473. [PMID: 31171788 PMCID: PMC6554308 DOI: 10.1038/s41467-019-10494-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/15/2019] [Indexed: 11/09/2022] Open
Abstract
There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in 224Rn and 226Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment.
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Dhaliwal S, Rybak I, Ellis S, Notay M, Trivedi M, Burney W, Vaughn A, Nguyen M, Reiter P, Bosanac S, Yan H, Foolad N, Sivamani R. Assessment of topical bakuchiol and retinol for facial photoageing. Br J Dermatol 2019. [DOI: 10.1111/bjd.17476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Dhaliwal S, Rybak I, Ellis S, Notay M, Trivedi M, Burney W, Vaughn A, Nguyen M, Reiter P, Bosanac S, Yan H, Foolad N, Sivamani R. 评估局部用补骨脂酚和视黄醇用于缓解面部光致老化的效果. Br J Dermatol 2019. [DOI: 10.1111/bjd.17489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Rosiak D, Seidlitz M, Reiter P, Naïdja H, Tsunoda Y, Togashi T, Nowacki F, Otsuka T, Colò G, Arnswald K, Berry T, Blazhev A, Borge MJG, Cederkäll J, Cox DM, De Witte H, Gaffney LP, Henrich C, Hirsch R, Huyse M, Illana A, Johnston K, Kaya L, Kröll T, Benito MLL, Ojala J, Pakarinen J, Queiser M, Rainovski G, Rodriguez JA, Siebeck B, Siesling E, Snäll J, Van Duppen P, Vogt A, von Schmid M, Warr N, Wenander F, Zell KO. Enhanced Quadrupole and Octupole Strength in Doubly Magic ^{132}Sn. PHYSICAL REVIEW LETTERS 2018; 121:252501. [PMID: 30608829 DOI: 10.1103/physrevlett.121.252501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 09/14/2018] [Indexed: 06/09/2023]
Abstract
The first 2^{+} and 3^{-} states of the doubly magic nucleus ^{132}Sn are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The ^{132}Sn ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a ^{206}Pb target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0_{g.s.}^{+}→2_{1}^{+}, 0_{g.s.}^{+}→3_{1}^{-}, and 2_{1}^{+}→3_{1}^{-} in ^{132}Sn. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0_{g.s.}^{+}→2_{1}^{+}) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of ^{132}Sn.
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Adamczak A, Antognini A, Berger N, Cocolios T, Dressler R, Eggenberger A, Eichler R, Indelicato P, Jungmann K, Kirch K, Knecht A, Papa A, Pohl R, Pospelov M, Rapisarda E, Reiter P, Ritjoho N, Roccia S, Severijns N, Skawran A, Wauters F, Willmann L. Nuclear structure with radioactive muonic atoms. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201819304014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Muonic atoms have been used to extract the most accurate nuclear charge radii based on the detection of X-rays from the muonic cascades. Most stable and a few unstable isotopes have been investigated with muonic atom spectroscopy techniques. A new research project recently started at the Paul Scherrer Institut aims to extend the highresolution muonic atom spectroscopy for the precise determination of nuclear charge radii and other nuclear structure properties of radioactive isotopes. The challenge to combine the high-energy muon beam with small quantity of stopping mass is being addressed by developing the concept of stopping the muon in a high-density, a high-pressure hydrogen cell and subsequent transfer of the muon to the element of interest. Status and perspectives of the project will be presented.
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Delafosse C, Verney D, Marević P, Gottardo A, Michelagnoli C, Lemasson A, Goasduff A, Ljungvall J, Clément E, Korichi A, De Angelis G, Andreoiu C, Babo M, Boso A, Didierjean F, Dudouet J, Franchoo S, Gadea A, Georgiev G, Ibrahim F, Jacquot B, Konstantinopoulos T, Lenzi SM, Maquart G, Matea I, Mengoni D, Napoli DR, Nikšić T, Olivier L, Pérez-Vidal RM, Portail C, Recchia F, Redon N, Siciliano M, Stefan I, Stezowski O, Vretenar D, Zielinska M, Barrientos D, Benzoni G, Birkenbach B, Boston AJ, Boston HC, Cederwall B, Charles L, Ciemala M, Collado J, Cullen DM, Désesquelles P, de France G, Domingo-Pardo C, Eberth J, González V, Harkness-Brennan LJ, Hess H, Judson DS, Jungclaus A, Korten W, Lefevre A, Legruel F, Menegazzo R, Million B, Nyberg J, Quintana B, Ralet D, Reiter P, Saillant F, Sanchis E, Theisen C, Valiente Dobon JJ. Pseudospin Symmetry and Microscopic Origin of Shape Coexistence in the ^{78}Ni Region: A Hint from Lifetime Measurements. PHYSICAL REVIEW LETTERS 2018; 121:192502. [PMID: 30468583 DOI: 10.1103/physrevlett.121.192502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 08/27/2018] [Indexed: 06/09/2023]
Abstract
Lifetime measurements of excited states of the light N=52 isotones ^{88}Kr, ^{86}Se, and ^{84}Ge 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 ^{84}Ge. While the B(E2;2^{+}→0^{+}) values of ^{88}Kr, ^{86}Se saturate the maximum quadrupole collectivity offered by the natural valence (3s, 2d, 1g_{7/2}, 1h_{11/2}) space of an inert ^{78}Ni core, the value obtained for ^{84}Ge largely exceeds it, suggesting that shape coexistence phenomena, previously reported at N≲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 ρ field in shell-structure evolution.
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Dhaliwal S, Rybak I, Ellis S, Notay M, Trivedi M, Burney W, Vaughn A, Nguyen M, Reiter P, Bosanac S, Yan H, Foolad N, Sivamani R. Prospective, randomized, double‐blind assessment of topical bakuchiol and retinol for facial photoageing. Br J Dermatol 2018; 180:289-296. [DOI: 10.1111/bjd.16918] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2018] [Indexed: 12/11/2022]
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Wilson J, Lebois M, Qi L, Amador-Celdran P, Bleuel D, Briz J, Carroll R, Catford W, Witte HD, Doherty D, Eloirdi R, Georgiev G, Gottardo A, Goasduff A, Hadyñska-Klek K, Hauschild K, Hess H, Ingeberg V, Konstantinopoulos T, Ljungvall J, Lopez-Martens A, Lorusso G, Lozeva R, Lutter R, Marini P, Matea I, Materna T, Mathieu L, Oberstedt A, Oberstedt S, Panebianco S, Podolyak Z, Porta A, Regan P, Reiter P, Rezynkina K, Rose S, Sahin E, Seidlitz M, Serot O, Shearman R, Siebeck B, Siem S, Smith A, Tveten G, Verney D, Warr N, Zeiser F, Zielinska M. Studies of fission fragment yields via high-resolution γ-ray spectroscopy. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201816900030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Precise spectroscopic information on the fast neutron induced fission of the 238U(n,f) reaction was recently gained using a new technique which involved coupling of the Miniball high resolution y-ray spectrometer and the LICORNE directional neutron source. The experiment allowed measurement of the isotopic fission yields for around 40 even-even nuclei at an incident neutron energy of around 2 MeV where yield data are very sparse. In addition spectroscopic information on very neutron-rich fission products was obtained. Results were compared to models, both the JEFF-3.1.1 data base and the GEF code, and large discrepancies for the S1 fission mode in the Sn/Mo isotope pair were discovered. This suggests that current models are overestimating the role played by spherical shell effects in fast neutron induced fission. In late 2017 and 2018 the nu-ball hybrid spectrometer will be constructed at the IPN Orsay to perform further experimental investigations with directional neutrons coupled to a powerful hybrid Ge/LaBr3 detector array. This will open up new possibilities for measurements of fission yields for fast-neutron-induced fission using the spectroscopic technique and will be complimentary to other methods being developed.
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Dudouet J, Lemasson A, Duchêne G, Rejmund M, Clément E, Michelagnoli C, Didierjean F, Korichi A, Maquart G, Stezowski O, Lizarazo C, Pérez-Vidal RM, Andreoiu C, de Angelis G, Astier A, Delafosse C, Deloncle I, Dombradi Z, de France G, Gadea A, Gottardo A, Jacquot B, Jones P, Konstantinopoulos T, Kuti I, Le Blanc F, Lenzi SM, Li G, Lozeva R, Million B, Napoli DR, Navin A, Petrache CM, Pietralla N, Ralet D, Ramdhane M, Redon N, Schmitt C, Sohler D, Verney D, Barrientos D, Birkenbach B, Burrows I, Charles L, Collado J, Cullen DM, Désesquelles P, Domingo Pardo C, González V, Harkness-Brennan L, Hess H, Judson DS, Karolak M, Korten W, Labiche M, Ljungvall J, Menegazzo R, Mengoni D, Pullia A, Recchia F, Reiter P, Salsac MD, Sanchis E, Theisen C, Valiente-Dobón JJ, Zielińska M. _{36}^{96}Kr_{60}-Low-Z Boundary of the Island of Deformation at N=60. PHYSICAL REVIEW LETTERS 2017; 118:162501. [PMID: 28474951 DOI: 10.1103/physrevlett.118.162501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Indexed: 06/07/2023]
Abstract
Prompt γ-ray spectroscopy of the neutron-rich ^{96}Kr, 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^{π}=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.
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17
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Ziegelwanger H, Reiter P, Conter M. The Three-Dimensional Quasi-Periodic Boundary Element Method: Implementation, Evaluation, and Use Cases. INTERNATIONAL JOURNAL OF COMPUTATIONAL METHODS AND EXPERIMENTAL MEASUREMENTS 2017. [DOI: 10.2495/cmem-v5-n3-404-414] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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18
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Miller R, Le-Rademacher J, Sio T, Leenstra J, Rine G, Curtis A, Singh A, Martenson J, Novotny R, Tan A, Reiter P, Loprinzi C. A Phase III, Randomized Double-Blind Study of Doxepin Rinse versus Magic Mouthwash versus Placebo in the Treatment of Acute Oral Mucositis Pain in Patients Receiving Head and Neck Radiotherapy with or without Chemotherapy (Alliance A221304). Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.09.047] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Podolyák Z, Shand CM, Lalović N, Gerl J, Rudolph D, Alexander T, Boutachkov P, Cortés ML, Górska M, Kojouharov I, Kurz N, Louchart C, Merchán E, Michelagnoli C, Pérez-Vidal RM, Pietri S, Ralet D, Reese M, Schaffner H, Stahl C, Weick H, Ameil F, de Angelis G, Arici T, Carroll R, Dombrádi Z, Gadea A, Golubev P, Lettmann M, Lizarazo C, Mahboub D, Pai H, Patel Z, Pietralla N, Regan PH, Sarmiento LG, Wieland O, Wilson E, Birkenbach B, Bruyneel B, Burrows I, Charles L, Clément E, Crespi FCL, Cullen DM, Désesquelles P, Eberth J, González V, Habermann T, Harkness-Brennan L, Hess H, Judson DS, Jungclaus A, Korten W, Labiche M, Maj A, Mengoni D, Napoli DR, Pullia A, Quintana B, Rainovski G, Reiter P, Salsac MD, Sanchis E, Valiente Dóbon JJ. Role of the Δ Resonance in the Population of a Four-Nucleon State in the ^{56}Fe→^{54}Fe Reaction at Relativistic Energies. PHYSICAL REVIEW LETTERS 2016; 117:222302. [PMID: 27925748 DOI: 10.1103/physrevlett.117.222302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Indexed: 06/06/2023]
Abstract
The ^{54}Fe nucleus was populated from a ^{56}Fe beam impinging on a Be target with an energy of E/A=500 MeV. The internal decay via γ-ray emission of the 10^{+} metastable state was observed. As the structure of this isomeric state has to involve at least four unpaired nucleons, it cannot be populated in a simple two-neutron removal reaction from the ^{56}Fe ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of ^{54}Fe, suggesting that it was populated via the decay of the Δ^{0} resonance into a proton. This process allows the population of four-nucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10^{+} metastable state in ^{54}Fe is a consequence of the quark structure of the nucleons.
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Clément E, Zielińska M, Görgen A, Korten W, Péru S, Libert J, Goutte H, Hilaire S, Bastin B, Bauer C, Blazhev A, Bree N, Bruyneel B, Butler PA, Butterworth J, Delahaye P, Dijon A, Doherty DT, Ekström A, Fitzpatrick C, Fransen C, Georgiev G, Gernhäuser R, Hess H, Iwanicki J, Jenkins DG, Larsen AC, Ljungvall J, Lutter R, Marley P, Moschner K, Napiorkowski PJ, Pakarinen J, Petts A, Reiter P, Renstrøm T, Seidlitz M, Siebeck B, Siem S, Sotty C, Srebrny J, Stefanescu I, Tveten GM, Van de Walle J, Vermeulen M, Voulot D, Warr N, Wenander F, Wiens A, De Witte H, Wrzosek-Lipska K. Erratum: Spectroscopic Quadrupole Moments in ^{96,98}Sr: Evidence for Shape Coexistence in Neutron-Rich Strontium Isotopes at N=60 [Phys. Rev. Lett. 116, 022701 (2016)]. PHYSICAL REVIEW LETTERS 2016; 117:099902. [PMID: 27610893 DOI: 10.1103/physrevlett.117.099902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Indexed: 06/06/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.116.022701.
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21
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Hadyńska-Klȩk K, Napiorkowski PJ, Zielińska M, Srebrny J, Maj A, Azaiez F, Valiente Dobón JJ, Kicińska-Habior M, Nowacki F, Naïdja H, Bounthong B, Rodríguez TR, de Angelis G, Abraham T, Anil Kumar G, Bazzacco D, Bellato M, Bortolato D, Bednarczyk P, Benzoni G, Berti L, Birkenbach B, Bruyneel B, Brambilla S, Camera F, Chavas J, Cederwall B, Charles L, Ciemała M, Cocconi P, Coleman-Smith P, Colombo A, Corsi A, Crespi FCL, Cullen DM, Czermak A, Désesquelles P, Doherty DT, Dulny B, Eberth J, Farnea E, Fornal B, Franchoo S, Gadea A, Giaz A, Gottardo A, Grave X, Grȩbosz J, Görgen A, Gulmini M, Habermann T, Hess H, Isocrate R, Iwanicki J, Jaworski G, Judson DS, Jungclaus A, Karkour N, Kmiecik M, Karpiński D, Kisieliński M, Kondratyev N, Korichi A, Komorowska M, Kowalczyk M, Korten W, Krzysiek M, Lehaut G, Leoni S, Ljungvall J, Lopez-Martens A, Lunardi S, Maron G, Mazurek K, Menegazzo R, Mengoni D, Merchán E, Mȩczyński W, Michelagnoli C, Mierzejewski J, Million B, Myalski S, Napoli DR, Nicolini R, Niikura M, Obertelli A, Özmen SF, Palacz M, Próchniak L, Pullia A, Quintana B, Rampazzo G, Recchia F, Redon N, Reiter P, Rosso D, Rusek K, Sahin E, Salsac MD, Söderström PA, Stefan I, Stézowski O, Styczeń J, Theisen C, Toniolo N, Ur CA, Vandone V, Wadsworth R, Wasilewska B, Wiens A, Wood JL, Wrzosek-Lipska K, Ziȩbliński M. Superdeformed and Triaxial States in ^{42}Ca. PHYSICAL REVIEW LETTERS 2016; 117:062501. [PMID: 27541463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Indexed: 06/06/2023]
Abstract
Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in ^{42}Ca were determined from E2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 0_{2}^{+} has been obtained and the role of triaxiality in the A∼40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time.
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Clément E, Zielińska M, Görgen A, Korten W, Péru S, Libert J, Goutte H, Hilaire S, Bastin B, Bauer C, Blazhev A, Bree N, Bruyneel B, Butler PA, Butterworth J, Delahaye P, Dijon A, Doherty DT, Ekström A, Fitzpatrick C, Fransen C, Georgiev G, Gernhäuser R, Hess H, Iwanicki J, Jenkins DG, Larsen AC, Ljungvall J, Lutter R, Marley P, Moschner K, Napiorkowski PJ, Pakarinen J, Petts A, Reiter P, Renstrøm T, Seidlitz M, Siebeck B, Siem S, Sotty C, Srebrny J, Stefanescu I, Tveten GM, Van de Walle J, Vermeulen M, Voulot D, Warr N, Wenander F, Wiens A, De Witte H, Wrzosek-Lipska K. Spectroscopic Quadrupole Moments in {96,98}Sr: Evidence for Shape Coexistence in Neutron-Rich Strontium Isotopes at N=60. PHYSICAL REVIEW LETTERS 2016; 116:022701. [PMID: 26824536 DOI: 10.1103/physrevlett.116.022701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Indexed: 06/05/2023]
Abstract
Neutron-rich {96,98}Sr isotopes have been investigated by safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility. Reduced transition probabilities and spectroscopic quadrupole moments have been extracted from the differential Coulomb excitation cross sections. These results allow, for the first time, the drawing of definite conclusions about the shape coexistence of highly deformed prolate and spherical configurations. In particular, a very small mixing between the coexisting states is observed, contrary to other mass regions where strong mixing is present. Experimental results have been compared to beyond-mean-field calculations using the Gogny D1S interaction in a five-dimensional collective Hamiltonian formalism, which reproduce the shape change at N=60.
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Lopez-Martens A, Henning G, Khoo T, Seweryniak D, Alcorta M, Asai M, Back B, Bertone P, Boilley D, Carpenter M, Chiara C, Chowdhury P, Gall B, Greenlees P, Gurdal G, Hauschild K, Heinz A, Hoffman C, Janssens R, Karpov A, Kay B, Kondev F, Lakshmi S, Lauristen T, Lister C, McCutchan E, Nair C, Piot J, Potterveld D, Reiter P, Rowley N, Rogers A, Zhu S. Stability and synthesis of superheavy elements: Fighting the battle against fission – example of 254No. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201613103001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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24
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Ceruti S, Camera F, Bracco A, Avigo R, Benzoni G, Blasi N, Bocchi G, Bottoni S, Brambilla S, Crespi FCL, Giaz A, Leoni S, Mentana A, Million B, Morales AI, Nicolini R, Pellegri L, Pullia A, Riboldi S, Wieland O, Birkenbach B, Bazzacco D, Ciemala M, Désesquelles P, Eberth J, Farnea E, Görgen A, Gottardo A, Hess H, Judson DS, Jungclaus A, Kmiecik M, Korten W, Maj A, Menegazzo R, Mengoni D, Michelagnoli C, Modamio V, Montanari D, Myalski S, Napoli D, Quintana B, Reiter P, Recchia F, Rosso D, Sahin E, Salsac MD, Söderström PA, Stezowski O, Theisen C, Ur C, Valiente-Dobón JJ, Zieblinski M. Isospin Mixing in ^{80}Zr: From Finite to Zero Temperature. PHYSICAL REVIEW LETTERS 2015; 115:222502. [PMID: 26650299 DOI: 10.1103/physrevlett.115.222502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Indexed: 06/05/2023]
Abstract
The isospin mixing was deduced in the compound nucleus ^{80}Zr at an excitation energy of E^{*}=54 MeV from the γ decay of the giant dipole resonance. The reaction ^{40}Ca+^{40}Ca at E_{beam}=136 MeV was used to form the compound nucleus in the isospin I=0 channel, while the reaction ^{37}Cl+^{44}Ca at E_{beam}=95 MeV was used as the reference reaction. The γ rays were detected with the AGATA demonstrator array coupled with LaBr_{3}:Ce detectors. The temperature dependence of the isospin mixing was obtained and the zero-temperature value deduced. The isospin-symmetry-breaking correction δ_{C} used for the Fermi superallowed transitions was extracted and found to be consistent with β-decay data.
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25
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Sotty C, Zielińska M, Georgiev G, Balabanski DL, Stuchbery AE, Blazhev A, Bree N, Chevrier R, Das Gupta S, Daugas JM, Davinson T, De Witte H, Diriken J, Gaffney LP, Geibel K, Hadyńska-Klek K, Kondev FG, Konki J, Kröll T, Morel P, Napiorkowski P, Pakarinen J, Reiter P, Scheck M, Seidlitz M, Siebeck B, Simpson G, Törnqvist H, Warr N, Wenander F. Publisher's Note: (37)(97)Rb(60): The Cornerstone of the Region of Deformation around A∼100 [Phys. Rev. Lett. 115, 172501 (2015)]. PHYSICAL REVIEW LETTERS 2015; 115:209902. [PMID: 26613483 DOI: 10.1103/physrevlett.115.209902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Indexed: 06/05/2023]
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