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Author Stahl, C. et al.; Gadea, A.
Title Population of the 2(ms)(+) mixed-symmetry state of Ba-140 with the alpha-transfer reaction Type Journal Article
Year 2015 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 92 Issue 4 Pages 044324 - 7pp
Keywords
Abstract Background: Identification of proton-neutron mixed-symmetric one-quadrupole phonon excitations (the 2(ms)(+) states) of atomic nuclei provides information on the isovector part of the residual nucleon-nucleon interaction. It was predicted that the 2(ms)(+) state of particular nuclei close to the U(5) limit of the interacting boson model, in particular Ba-140, should be considerably populated by alpha-transfer reactions [C. E. Alonso et al., Phys. Rev. C 78, 017301 (2008)]. Purpose: We aim at the identification of the 2(ms)(+) mixed-symmetry state (MSS) of radioactive Ba-140 and investigate its population by the alpha-transfer reaction as a suitable tool to selectively populate MSSs and as a potential new signature for its mixed-symmetric character. Method: A gamma-ray spectroscopy experiment was performed in inverse kinematics in order to populate the 2(ms)(+) state of Ba-140 by alpha-transfer from a C-nat target on Xe-136 beam ions. The population of the candidate for the 2(ms)(+) state of Ba-140 was measured relative to the population of the 2(1)(+) state. Results: The candidate for the 2(ms)(+) state of Ba-140 was populated by a transfer three times weaker than predicted. Another 2(+) state that can be ruled out as the MSS was in turn as strongly populated by the a transfer as predicted for the MSS. Conclusions: The relative population of 2(+) states by alpha-transfer cannot serve as a new signature for MSSs, since other 2(+) states are also strongly populated. Nevertheless, the substantial population of the MSS candidate of Ba-140 by alpha transfer qualifies this type of reaction as suitable tool to excite MSSs and study their electromagnetic decay properties.
Address [Stahl, C.; Leske, J.; Bauer, C.; John, P. R.; Pietralla, N.; Reese, M.] Tech Univ Darmstadt, Inst Kernphys, D-64291 Darmstadt, Germany, Email: stahl@ikp.tu-darmstadt.de
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000363524900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2418
Permanent link to this record
 
 
Author Birkenbach, B. et al; Gadea, A.
Title Spectroscopy of the neutron-rich actinide nucleus U-240 following multinucleon-transfer reactions Type Journal Article
Year 2015 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 92 Issue 4 Pages 044319 - 9pp
Keywords
Abstract Background: Nuclear structure information for the neutron-rich actinide nuclei is important since it is the benchmark for theoretical models that provide predictions for the heaviest nuclei. Purpose: gamma-ray spectroscopy of neutron-rich heavy nuclei in the actinide region. Method: Multinucleon-transfer reactions in Zn-70 + U-238 and Xe-136 + U-238 have been measured in two experiments performed at the INFN Legnaro, Italy. In the Zn-70 experiment the high-resolution HPGe Clover Array (CLARA) coupled to the magnetic spectrometer PRISMA was employed. In the Xe-136 experiment the high-resolution Advanced Gamma Tracking Array (AGATA) was used in combination with PRISMA and the Detector Array for Multinucleon Transfer Ejectiles (DANTE). Results: The ground-state band (g.s. band) of U-240 was measured up to the 20(+) level and a tentative assignment was made up to the (24(+)) level. Results from gamma gamma coincidence and from particle coincidence analyses are shown. Moments of inertia (MoI) show a clear upbend. Evidence for an extended first negative-parity band of U-240 is found. Conclusions: A detailed comparison with latest calculations shows best agreement with cranked relativistic Hartree-Bogoliubov (CRHB) calculations for the g.s. band properties. The negative-parity band shows the characteristics of a K-pi = 0 band based on an octupole vibration.
Address [Birkenbach, B.; Vogt, A.; Geibel, K.; Reiter, P.; Eberth, J.; Hess, H.; Jolie, J.; Radeck, F.; Steinbach, T.; Wiens, A.] Univ Cologne, Inst Kernphys, D-50937 Cologne, Germany, Email: birkenbach@ikp.uni-koeln.de
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000363236900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2421
Permanent link to this record
 
 
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
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
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000368298200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2522
Permanent link to this record
 
 
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
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
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000551404600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4471
Permanent link to this record
 
 
Author Sahin, E. et al; Gadea, A.; Algora, A.
Title Structure of the N=50 As, Ge, Ga nuclei Type Journal Article
Year 2012 Publication Nuclear Physics A Abbreviated Journal Nucl. Phys. A
Volume 893 Issue Pages 1-12
Keywords NUCLEAR REACTIONS U-238(Se-82, Ga-81), (Se-82, Ge-82), (Se-82, As-83), E=515 MeV; measured E-gamma, I-gamma (theta), gamma gamma-coin, reaction fragments, (fragment)gamma-coin using PRISMA magnetic spectrometer, gamma after deexcitation using Ge Compton-suppressed detectors of CLARA array, thin and thick target; deduced sigma(theta), levels, J, pi; calculated levels, J, pi using shell model
Abstract The level structures of the N = 50 As-83, Ge-82, and Ga-81 isotones have been investigated by means of multi-nucleon transfer reactions. A first experiment was performed with the CLARA PRISMA setup to identify these nuclei. A second experiment was carried out with the GASP array in order to deduce the gamma-ray coincidence information. The results obtained on the high-spin states of such nuclei are used to test the stability of the N = 50 shell closure in the region of Ni-78 (Z = 28). The comparison of the experimental level schemes with the shell-model calculations yields an N = 50 energy gap value of 4.7(3) MeV at Z = 28. This value, in a good agreement with the prediction of the finite-range liquid-drop model as well as with the recent large-scale shell model calculations, does not support a weakening of the N = 50 shell gap down to Z = 28.
Address [Sahin, E.; de Angelis, G.; Gadea, A.; Corradi, L.; Fioretto, E.; Gottardo, A.; Guiot, B.; Modamio, V.; Napoli, D. R.; Silvestri, R.; Stefanini, A. M.; Valiente-Dobon, J. J.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Italy, Email: eda.sahin@lnl.infn.it
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0375-9474 ISBN Medium
Area Expedition Conference
Notes WOS:000310091000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1191
Permanent link to this record
 
 
Author Pajtler, M.V.; Szilner, S.; Corradi, L.; de Angelis, G.; Fioretto, E.; Gadea, A.; Haas, F.; Lunardi, S.; Malenica, D.J.; Marginean, N.; Mengoni, D.; Mijatovic, T.; Montagnoli, G.; Montanari, D.; Pollarolo, G.; Recchia, F.; Salsac, M.D.; Scarlassara, F.; Soic, N.; Stefanini, A.M.; Ur, C.A.; Valiente-Dobon, J.J.
Title Selective properties of neutron transfer reactions in the Zr-90+Pb-208 system for the population of excited states in zirconium isotopes Type Journal Article
Year 2015 Publication Nuclear Physics A Abbreviated Journal Nucl. Phys. A
Volume 941 Issue Pages 273-292
Keywords Heavy ion transfer reactions; gamma transitions; Magnetic spectrometer
Abstract Nuclei produced via multineutron transfer channels have been studied in Zr-90 + Pb-208 close to the Coulomb barrier energy in a fragment-gamma coincident measurement employing the PRISMA magnetic spectrometer coupled to the CLARA gamma-array. The selective properties of the reaction mechanism have been discussed in terms of states and their strength excited in the neutron transfer channels leading to Zr89-94 isotopes. A strong population of yrast states, with energies up to similar to 7.5 MeV has been observed.
Address [Pajtler, M. Varga] Univ Osijek, Dept Phys, HR-31000 Osijek, Croatia, Email: mvarga@fizika.unios.hr;
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0375-9474 ISBN Medium
Area Expedition Conference
Notes WOS:000360515100020 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2377
Permanent link to this record
 
 
Author Montanari, D. et al; Gadea, A.
Title Probing the nature of particle-core couplings in Ca-49 with gamma spectroscopy and heavy-ion transfer reactions Type Journal Article
Year 2011 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 697 Issue 4 Pages 288-293
Keywords Multi-nucleon transfer; Gamma spectroscopy; Magnetic spectrometer; Particle-core coupling
Abstract Neutron rich nuclei around Ca-48 have been measured with the CLARA-PRISMA setup, making use of Ca-48 on Ni-64 binary reactions, at 5.9 MeV/A. Angular distributions of gamma rays give evidence, in several transfer channels, for a large spin alignment (approximate to 70%) perpendicular to the reaction plane, making it possible to firmly establish spin and parities of the excited states. In the case of Ca-49, states arising from different types of particle-core couplings are, for the first time, unambiguously identified on basis of angular distribution, polarization and lifetime measurements. Shell model and particle-vibration coupling calculations are used to pin down the nature of the states. Evidence is found for the presence, in the same excitation energy region, of two types of coupled states, i.e. single particle coupled to either Ca-48 or Ca-50 simple configurations, and particle-vibration coupled states based on the 3- phonon of Ca-48.
Address [Montanari, D.; Leoni, S.; Bocchi, G.; Bortignon, P. F.; Bracco, A.; Camera, F.; Colo, G.; Corsi, A.; Crespi, F. C. L.; Nicolini, R.] Univ Milan, Dipartimento Fis, Milan, Italy, Email: silvia.leoni@mi.infn.it
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0370-2693 ISBN Medium
Area Expedition Conference
Notes ISI:000288300400005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 542
Permanent link to this record
 
 
Author Benzoni, G. et al; Gadea, A.; Algora, A.
Title First measurement of beta decay half-lives in neutron-rich Tl and Bi isotopes Type Journal Article
Year 2012 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 715 Issue 4-5 Pages 293-297
Keywords
Abstract Neutron-rich isotopes around lead, beyond N = 126, have been studied exploiting the fragmentation of an uranium primary beam at the FRS-RISING setup at GSI. For the first time beta-decay half-lives of Bi-219 and Tl-211,Tl-212,Tl-213 isotopes have been derived. The half-lives have been extracted using a numerical simulation developed for experiments in high-background conditions. Comparison with state of the art models used in r-process calculations is given, showing a systematic underestimation of the experimental values, at variance from close-lying nuclei.
Address [Benzoni, G.; Morales, A. I.; Bracco, A.; Camera, F.; Crespi, F. C. L.; Corsi, A. M.; Leoni, S.; Million, B.; Nicolini, R.; Wieland, O.] Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy, Email: giovanna.benzoni@mi.infn.it
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000308617500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1148
Permanent link to this record
 
 
Author Gottardo, A. et al; Gadea, A.; Algora, A.
Title New μs isomers in the neutron-rich Hg-210 nucleus Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 725 Issue 4-5 Pages 292-296
Keywords
Abstract Neutron-rich nuclei in the lead region, beyond N = 126, have been studied at the FRS-RISING setup at GSI, exploiting the fragmentation of a primary uranium beam. Two isomeric states have been identified in Hg-210: the 8(+) isomer expected from the seniority scheme in the vg(9/2) shell and a second one at low spin and low excitation energy. The decay strength of the 8(+) isomer confirms the need of effective three-body forces in the case of neutron-rich lead isotopes. The other unexpected low-lying isomer has been tentatively assigned as a 3(-) state, although this is in contrast with theoretical expectations.
Address [Gottardo, A.; Valiente-Dobon, J. J.; de Angelis, G.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Legnaro, Italy, Email: andrea.gottardo@lnl.infn.it
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000324223100014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1588
Permanent link to this record
 
 
Author Taprogge, J. et al; Gadea, A.; Montaner-Piza, A.
Title Identification of a millisecond isomeric state in Cd-129(81) via the detection of internal conversion and Compton electrons Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 738 Issue Pages 223-227
Keywords Isomeric decays; Transition strengths; Shell model calculations
Abstract The decay of an isomeric state in the neutron-rich nucleus Cd-129 has been observed via the detection of internal conversion and Compton electrons providing first experimental information on excited states in this nucleus. The isomer was populated in the projectile fission of a U-238 beam at the Radioactive Isotope Beam Factory at RIKEN. From the measured yields of gamma-rays and internal conversion electrons, a multipolarity of E3 was tentatively assigned to the isomeric transition. A half-life of T-1/2 = 3.6(2) ms was determined for the new state which was assigned a spin of (21/2(+)), based on a comparison to shell model calculations performed using state-of-the-art realistic effective interactions.
Address [Taprogge, J.; Jungclaus, A.] CSIC, Inst Estruct Mat, Madrid 28006, Spain, Email: andrea.jungclaus@csic.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (down) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000344624900036 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2021
Permanent link to this record