| |
Records |
Links |
|
Author |
Jaworski, G.; Palacz, M.; Nyberg, J.; de Angelis, G.; de France, G.; Di Nitto, A.; Egea, F.J.; Erduran, M.N.; Erturk, S.; Farnea, E.; Gadea, A.; Gonzalez, V.; Gottardo, A.; Huyuk, T.; Kownacki, J.; Pipidis, A.; Roeder, B.; Soderstrom, P.A.; Sanchis, E.; Tarnowski, R.; Triossi, A.; Wadsworth, R.; Valiente-Dobon, J.J. |
|
| |
Title |
Monte Carlo simulation of a single detector unit for the neutron detector array NEDA |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
|
| |
Volume |
673 |
Issue |
|
Pages |
64-72 |
|
| |
Keywords |
Monte Carlo simulation; BC501; BC501A; BC537; Liquid scintillator; Neutron detector; Geant4; NEDA |
|
| |
Abstract  |
A study of the dimensions and performance of a single detector of the future neutron detector array NEDA was performed by means of Monte Carlo simulations, using GEANT4. Two different liquid scintillators were evaluated: the hydrogen based BC501A and the deuterated BC537. The efficiency and the probability that one neutron will trigger a signal in more than one detector were investigated as a function of the detector size. The simulations were validated comparing the results to experimental measurements performed with two existing neutron detectors, with different geometries, based on the liquid scintillator BC501. |
|
| |
Address |
[Jaworski, G.; Palacz, M.; Kownacki, J.; Tarnowski, R.] Univ Warsaw, Heavy Ion Lab, PL-02093 Warsaw, Poland, Email: palacz@slcj.uw.edu.pl |
|
| |
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 |
0168-9002 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000301813500009 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
944 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
AGATA Collaboration (Hadynska-Klek, K. et al); Gadea, A. |
|
| |
Title |
Quadrupole collectivity in Ca-42 from low-energy Coulomb excitation with AGATA |
Type |
Journal Article |
| |
Year |
2018 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
| |
Volume |
97 |
Issue |
2 |
Pages |
024326 - 20pp |
|
| |
Keywords |
|
|
| |
Abstract |
ACoulomb-excitation experiment to study electromagnetic properties of Ca-42 was performed using a 170-MeV calcium beam from the TANDEM XPU facility at INFN Laboratori Nazionali di Legnaro. gamma rays from excited states in Ca-42 were measured with the AGATA spectrometer. The magnitudes and relative signs of ten E2 matrix elements coupling six low-lying states in Ca-42, including the diagonal E2 matrix elements of 2(1)(+) and 2(2)(+) states, were determined using the least-squares code GOSIA. The obtained set of reduced E2 matrix elements was analyzed using the quadrupole sum rule method and yielded overall quadrupole deformation for 0(1),(+)(2) and 2(1,2)(+) states, as well as triaxiality for 0(1,2)(+) states, establishing the coexistence of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in Ca-42. The experimental results were compared with the state-of-the-art large-scale shell-model and beyond-mean-field calculations, which reproduce well the general picture of shape coexistence in Ca-42. |
|
| |
Address |
[Hadynska-Klek, K.; Napiorkowski, P. J.; Zielinska, M.; Srebrny, J.; Abraham, T.; Iwanicki, J.; Jaworski, G.; Kisielinski, M.; Komorowska, M.; Kowalczyk, M.; Ozmen, S. F.; Palacz, M.; Prochniak, L.; Rusek, K.; Wrzosek-Lipska, K.] Univ Warsaw, Heavy Ion Lab, Pasteura 5A, PL-02093 Warsaw, Poland, Email: katarzyna.hadynska@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 |
2469-9985 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000425604200003 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
3506 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Gosta G. et al.; Gadea, A. |
|
| |
Title |
Probing isospin mixing with the giant dipole resonance in the Zn-60 compound nucleus |
Type |
Journal Article |
| |
Year |
2021 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
| |
Volume |
103 |
Issue |
4 |
Pages |
L041302 - 6pp |
|
| |
Keywords |
|
|
| |
Abstract |
An experimental study of the isospin mixing in the mass region A = 60 was made by measuring the gamma decay from the giant dipole resonance in the compound nuclei Zn-60 and Zn-62. These compound nuclei were populated at two different excitation energies, E* = 47 MeV and E* = 58 MeV using the fusion evaporation reactions S-32 + Si-28 at the bombarding energy of 86 and 110 MeV and S-32 + Si-30 at 75 and 98 MeV. In the experiment, performed at the Laboratori Nazionali di Legnaro of the Istituto Nazionale di Fisica Nucleare (INFN), the gamma rays were measured with the GALILEO detection system in which large-volume LaBr3(Ce) detectors were added to the HPGe detectors. The Coulomb spreading width was obtained from the comparison of the two reactions and then the isospin mixing parameter at zero temperature and the isospin-symmetry-breaking correction for beta decay were deduced. The present results were compared with data of the same type in other mass regions and with data from mass and beta-decay measurements and with theory. The present data allow us to deduce for the first time a consistent picture for mass dependence of isospin mixing and for the corresponding correction for the beta decay, supporting a reliable extension to the very interesting region of Sn-100. |
|
| |
Address |
[Gosta, G.; Mentana, A.; Camera, F.; Bracco, A.; Capra, S.; Crespi, F. C. L.; Leoni, S.; Riboldi, S.; Porzio, C.; Ziliani, S.] Univ Milan, Dipartimento Fis, Milan, Italy, Email: Franco.Camera@mi.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 |
2469-9985 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000647600600009 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
4826 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Colovic, P. et al; Gadea, A. |
|
| |
Title |
Stretched configuration of states as inferred from gamma-ray angular distributions in Ar-40+Pb-208 neutron transfer reactions |
Type |
Journal Article |
| |
Year |
2017 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
|
| |
Volume |
53 |
Issue |
8 |
Pages |
166 - 6pp |
|
| |
Keywords |
|
|
| |
Abstract |
Angular distributions of.-rays for selected transitions in Ar-40,Ar-41,Ar-42 isotopes have been studied with the PRISMA magnetic spectrometer coupled to the CLARA gamma array. These transitions were populated in Ar isotopes reached via neutron transfer in the Ar-40 + Pb-208 reaction. By comparison with the shape of the experimental angular distribution of the known E2 transitions we established more firmly the spin and parity of excited states. In particular, in Ar-41 for the (11/2(-)) state through the (11/2(-)) -> 7/2(-) transition whose structure was discussed in terms of a phonon-fermion coupled state. The comparison with the expected fully aligned spin indicated that a high level of spin alignment has been reached. |
|
| |
Address |
[Colovic, P.; Szilner, S.; Mijatovic, T.; Malenica, D. Jelavic; Soic, N.] Rudjer Boskovic Inst, Zagreb, Croatia, Email: petra.colovic@irb.hr |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1434-6001 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000408433900002 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
3251 |
|
| Permanent link to this record |
| |
|
| |
|
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 |
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 |
PreSPEC and AGATA Collaborations (Ralet, D. et al); Domingo-Pardo, C.; Gadea, A.; Huyuk, T. |
|
| |
Title |
Lifetime measurement of neutron-rich even-even molybdenum isotopes |
Type |
Journal Article |
| |
Year |
2017 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
| |
Volume |
95 |
Issue |
3 |
Pages |
034320 - 11pp |
|
| |
Keywords |
|
|
| |
Abstract |
Background: In the neutron-rich A approximate to 100 mass region, rapid shape changes as a function of nucleon number as well as coexistence of prolate, oblate, and triaxial shapes are predicted by various theoretical models. Lifetime measurements of excited levels in the molybdenum isotopes allow the determination of transitional quadrupole moments, which in turn provides structural information regarding the predicted shape change. Purpose: The present paper reports on the experimental setup, the method that allowed one to measure the lifetimes of excited states in even-even molybdenum isotopes from mass A = 100 up to mass A = 108, and the results that were obtained. Method: The isotopes of interest were populated by secondary knock-out reaction of neutron-rich nuclei separated and identified by the GSI fragment separator at relativistic beam energies and detected by the sensitive PreSPEC-AGATA experimental setup. The latter included the Lund-York-Cologne calorimeter for identification, tracking, and velocity measurement of ejectiles, and AGATA, an array of position sensitive segmented HPGe detectors, used to determine the interaction positions of the gamma ray enabling a precise Doppler correction. The lifetimes were determined with a relativistic version of the Doppler-shift-attenuation method using the systematic shift of the energy after Doppler correction of a gamma-ray transition with a known energy. This relativistic Doppler-shift-attenuation method allowed the determination of mean lifetimes from 2 to 250 ps. Results: Even-even molybdenum isotopes from mass A = 100 to A = 108 were studied. The decays of the low-lying states in the ground-state band were observed. In particular, two mean lifetimes were measured for the first time: tau = 29.7(-9.1)(+11.3) ps for the 4(+) state of Mo-108 and tau = 3.2(-0.7)(+ 0.7) ps for the 6(+) state of Mo-102. Conclusions: The reduced transition strengths B(E2), calculated from lifetimes measured in this experiment, compared to beyond-mean-field calculations, indicate a gradual shape transition in the chain of molybdenum isotopes when going from A = 100 to A = 108 with a maximum reached at N = 64. The transition probabilities decrease for Mo-108 which may be related to its well-pronounced triaxial shape indicated by the calculations. |
|
| |
Address |
[Ralet, D.; Cortes, M. L.; Gregor, E.; Guastalla, G.; Givechev, A.; Habermann, T.; Louchart-Henning, C.; Merchan, E.; Pietralla, N.; Reese, M.; Singh, P. P.; Stahl, C.] Tech Univ Darmstadt, Inst Kernphys, D-64289 Darmstadt, Germany, Email: ralet@csnsm.in2p3.fr |
|
| |
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 |
2469-9985 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000399143200002 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
3045 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vogt, A. et al; Gadea, A. |
|
| |
Title |
Light and heavy transfer products in Xe-136+U-238 multinucleon transfer reactions |
Type |
Journal Article |
| |
Year |
2015 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
| |
Volume |
92 |
Issue |
2 |
Pages |
024619 - 12pp |
|
| |
Keywords |
|
|
| |
Abstract |
Background: Multinucleon transfer reactions (MNT) are a competitive tool to populate exotic neutron-rich nuclei in a wide region of nuclei, where other production methods have severe limitations or cannot be used at all. Purpose: Experimental information on the yields of MNT reactions in comparison with theoretical calculations are necessary to make predictions for the production of neutron-rich heavy nuclei. It is crucial to determine the fraction of MNT reaction products which are surviving neutron emission or fission at the high excitation energy after the nucleon exchange. Method: Multinucleon transfer reactions in Xe-136 + U-238 have been measured in a high-resolution gamma-ray/particle coincidence experiment. The large solid-angle magnetic spectrometer PRISMA coupled to the high-resolution Advanced Gamma Tracking Array (AGATA) has been employed. Beamlike reaction products after multinucleon transfer in the Xe region were identified and selected with the PRISMA spectrometer. Coincident particles were tagged by multichannel plate detectors placed at the grazing angle of the targetlike recoils inside the scattering chamber. Results: Mass yields have been extracted and compared with calculations based on the GRAZING model for MNT reactions. Kinematic coincidences between the binary reaction products, i.e., beamlike and targetlike nuclei, were exploited to obtain population yields for nuclei in the actinide region and compared to x-ray yields measured by AGATA. Conclusions: No sizable yield of actinide nuclei beyond Z = 93 is found to perform nuclear structure investigations. In-beam gamma-ray spectroscopy is feasible for few-neutron transfer channels in U and the -2p channel populating Th isotopes. |
|
| |
Address |
[Vogt, A.; Birkenbach, B.; Reiter, P.; Eberth, J.; Geibel, K.; Hess, H.; Jolie, J.; Radeck, F.; Steinbach, T.; Wiens, A.] Univ Cologne, Inst Kernphys, D-50937 Cologne, Germany, Email: andreas.vogt@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 |
0556-2813 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000360123600003 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
2373 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
AGATA Collaboration (Louchart, C. et al); Gadea, A.; Huyuk, T. |
|
| |
Title |
Collective nature of low-lying excitations in 70,72,74Zn from lifetime measurements using the AGATA spectrometer demonstrator |
Type |
Journal Article |
| |
Year |
2013 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
|
| |
Volume |
87 |
Issue |
5 |
Pages |
054302 - 10pp |
|
| |
Keywords |
|
|
| |
Abstract |
Background: Neutron-rich nuclei with protons in the fp shell show an onset of collectivity around N=40. Spectroscopic information is required to understand the underlying mechanism and to determine the relevant terms of the nucleon-nucleon interaction that are responsible for the evolution of the shell structure in this mass region. Methods: We report on the lifetime measurement of the first 2+ and 4+ states in 70,72,74Zn and the first 6+ state in 72Zn using the recoil distance Doppler shift method. The experiment was carried out at the INFN Laboratory of Legnaro with the AGATA demonstrator, first phase of the Advanced Gamma Tracking Array of highly segmented, high-purity germanium detectors coupled to the PRISMA magnetic spectrometer. The excited states of the nuclei of interest were populated in the deep inelastic scattering of a 76Ge beam impinging on a 238U target. Results: The maximum of collectivity along the chain of Zn isotopes is observed for 72Zn at N=42. An unexpectedly long lifetime of 20−5.2+1.8 ps was measured for the 4+ state in 74Zn. Conclusions: Our results lead to small values of the B(E2;41+→21+)/B(E2;21+→01+) ratio for 72,74Zn, suggesting a significant noncollective contribution to these excitations. These experimental results are not reproduced by state-of-the-art microscopic models and call for lifetime measurements beyond the first 2+ state in heavy zinc and nickel isotopes. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1638 |
|
| 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 |
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 |
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 |
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 |
