Records |
Author |
Ertoprak, A. et al; Algora, A.; Gadea, A.; Huyuk, T. |
Title |
M1 and E2 transition rates from core-excited states in semi-magic Ru-94 |
Type |
Journal Article |
Year |
2018 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
Volume |
54 |
Issue |
9 |
Pages |
145 - 9pp |
Keywords |
|
Abstract |
Lifetimes of high-spin states have been measured in the semi-magic (N = 50) nucleus Ru-94. Excited states in Ru-94 were populated in the Ni-58(Ca-40, 4p)Ru-94* fusion-evaporation reaction at the Grand Accelerateur National d'Ions Lourds (GANIL) accelerator complex. DSAM lifetime analysis was performed on the Doppler broadened line shapes in energy spectra obtained from gamma-rays emitted while the residual nuclei were slowing down in a thick 6 mg/cm(2) metallic Ni-58 target. In total eight excited-state lifetimes in the angular momentum range I = (13-20)h have been measured, five of which were determined for the first time. The corresponding B(M1) and B(E2) reduced transition strengths are discussed within the framework of large-scale shell model calculations to study the contribution of different particle-hole configurations, in particular for analyzing contributions from core-excited configurations. |
Address |
[Ertoprak, A.; Cederwall, B.; Qi, C.; Doncel, M.; Jakobsson, U.; Atac, A.; Back, T.; Moradi, F. Ghazi; Li, H.] Royal Inst Technol KTH, Dept Phys, SE-10691 Stockholm, Sweden, Email: ertoprak@kth.se |
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:000443091000003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3704 |
Permanent link to this record |
|
|
|
Author |
AGATA Collaboration (Avigo, R. et al); Domingo-Pardo, C.; Gadea, A.; Gonzalez, V. |
Title |
Low-lying electric dipole gamma-continuum for the unstable Fe-62(,)64 nuclei: Strength evolution with neutron number |
Type |
Journal Article |
Year |
2020 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
811 |
Issue |
|
Pages |
135951 - 6pp |
Keywords |
Fe-64; Fe-62; Nuclear structure; Dipole excitation around neutron threshold |
Abstract |
The gamma-ray emission from the nuclei Fe-62,Fe-64 following Coulomb excitation at bombarding energy of 400-440 AMeV was measured with special focus on E1 transitions in the energy region 4-8 MeV. The unstable neutron-rich nuclei Fe-62,Fe-64 were produced at the FAIR-GSI laboratories and selected with the FRS spectrometer. The gamma decay was detected with AGATA. From the measured gamma-ray spectra the summed E1 strength is extracted and compared to microscopic quasi-particle phonon model calculations. The trend of the E1 strength with increasing neutron number is found to be fairly well reproduced with calculations that assume a rather complex structure of the 1(-) states (three-phonon states) inducing a strong fragmentation of the E1 nuclear response below the neutron binding energy. |
Address |
[Avigo, R.; Wieland, O.; Bracco, A.; Camera, F.; Benzoni, G.; Blasi, N.; Bottoni, S.; Brambilla, S.; Crespi, F. C. L.; Leoni, S.; Million, B.; Morales, A., I; Pullia, A.; Riboldi, S.] Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy, Email: oliver.wieland@mi.infn.it |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0370-2693 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000612225400080 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4700 |
Permanent link to this record |
|
|
|
Author |
Fernandez, A.; Hufschmidt, D.; Colaux, J.L.; Valiente-Dobon, J.J.; Godinho, V.; Jimenez de Haro, M.C.; Feria, D.; Gadea, A.; Lucas, S. |
Title |
Low gas consumption fabrication of He-3 solid targets for nuclear reactions |
Type |
Journal Article |
Year |
2020 |
Publication |
Materials & Design |
Abbreviated Journal |
Mater. Des. |
Volume |
186 |
Issue |
|
Pages |
108337 - 10pp |
Keywords |
He-3 solid targets; Quasistatic magnetron sputtering; Low gas consumption; Nuclear reactions; Inverse kinematics; Target stability |
Abstract |
Nanoporous solids that stabilize trapped gas nanobubbles open new possibilities to fabricate solid targets for nuclear reactions. A methodology is described based on the magnetron sputtering (MS) technique operated under quasistatic flux conditions to produce such nanocomposites films with He-3 contents of up to 16 at.% in an amorphous-silicon matrix. In addition to the characteristic low pressure (3-6 Pa) needed for the gas discharge, the method ensures almost complete reduction of the process gas flow during film fabrication. The method could produce similar materials to those obtained under classical dynamic flux conditions for MS. The drastic reduction (>99.5%) of the gas consumption is fundamental for the fabrication of targets with scarce and expensive gases. Si:He-3 and W:He-3 targets are presented together with their microstructural (scanning and transmission electron microscopy, SEM and TEM respectively) and compositional (Ion Beam Analysis, IBA) characterization. The He-3 content achieved was over 1 x 10(18) at/cm(2) for film thicknesses between 1.5 and 3 μm for both Si and W matrices. First experiments to probe the stability of the targets for nuclear reaction studies in inverse kinematics configurations are presented. |
Address |
[Fernandez, Asuncion; Hufschmidt, Dirk; Godinho, Vanda; Jimenez de Haro, Maria C.; Feria, David] Univ Seville, CSIC, Inst Ciencia Mat Sevilla, Avda Amer Vespucio 49, Seville 41092, Spain, Email: asuncion@icmse.csic.es |
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Sci Ltd |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0264-1275 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000505221700053 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4239 |
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 |
Ertoprak, A. et al; Algora, A.; Gadea, A.; Huyuk, T. |
Title |
Lifetimes of core-excited states in semi-magic Rh-95 |
Type |
Journal Article |
Year |
2020 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
Volume |
56 |
Issue |
11 |
Pages |
291 - 8pp |
Keywords |
|
Abstract |
Lifetimes of negative-parity states have been determined in the neutron deficient semi-magic (N = 50) nucleus Rh-95. The fusion-evaporation reaction Ni-58(Ca-40, 3p) was used to populate high-spin states in Rh-95 at the Grand Accelerateur National d'Ions Lourds (GANIL) accelerator facility. The results were obtained using the Doppler Shift Attenuation Method (DSAM) based on the Doppler broadened line shapes produced during the slowing down process of the residual nuclei in a thick 6 mg/cm(2) metallic target. B(M1) and B(E2) reduced transition strengths are compared with predictions from large-scale shell-model calculations. state-of-the-art theory. Remarkably, the structural features up to moderate angular momentum of nuclei immediately below the N = Z = 50 shell closures can be described with high accuracy in a very simple way by shell-model calculations including only the g(9/2) and p(1/2) subshells. Of special interest is the neutron-proton pair coupling scheme which is expected to appear in the heaviest N=Z nuclei [1,2] and the seniority structure of the N = 50 isotones [3-7]. However, multiple core-excited states have been observed in the semi-magic nuclei of the Sn-100 region [8-10]. The theoretical study of those states is a challenging task, which requires a significantly larger model space for their interpretation. Transition probabilities between nuclear states provide important constraints for theoretical modelling of the structure of the nuclei of interest. Our previous lifetime study of the semimagic (N = 50) nucleus Ru-94 [ 11,12] provided information on the electromagnetic decay properties of neutron-core excited states. We now address lifetime measurements in its closest, more neutron deficient, isotone Rh-95 using the same DSAM technique. The experimental results have been interpreted within the framework of large-scale shell-model (LSSM) calculations. |
Address |
[Ertoprak, A.; Qi, C.; Cederwall, B.; Doncel, M.; Jakobsson, U.; Atac, A.; Back, T.; Ghazi Moradi, F.; Li, H.] Royal Inst Technol KTH, Dept Phys, S-10691 Stockholm, Sweden, Email: ertoprak@kth.se |
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:000590264900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4612 |
Permanent link to this record |