| Records |
| Author |
Morales, A.I.; Algora, A.; Molina, F.; Rubio, B. |
Title  |
Half-Life Systematics across the N=126 Shell Closure: Role of First-Forbidden Transitions in the beta Decay of Heavy Neutron-Rich Nuclei |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
113 |
Issue |
2 |
Pages |
022702 - 5pp |
| Keywords |
|
| Abstract |
This Letter reports on a systematic study of beta-decay half-lives of neutron-rich nuclei around doubly magic Pb-208. The lifetimes of the 126-neutron shell isotone Pt-204 and the neighboring Ir200-202, Pt-203, Au-204 are presented together with other 19 half-lives measured during the “stopped beam” campaign of the rare isotope investigations at GSI collaboration. The results constrain the main nuclear theories used in calculations of r-process nucleosynthesis. Predictions based on a statistical macroscopic description of the first-forbidden beta strength reveal significant deviations for most of the nuclei with N < 126. In contrast, theories including a fully microscopic treatment of allowed and first-forbidden transitions reproduce more satisfactorily the trend in the measured half-lives for the nuclei in this region, where the r-process pathway passes through during beta decay back to stability. |
| Address |
[Morales, A. I.; Benlliure, J.; Kurtukian-Nieto, T.; Verma, S.; Casarejos, E.; Alvarez-Pol, H.; Estevez-Aguado, M. E.] Univ Santiago de Compostela, E-15782 Santiago De Compostela, Spain, Email: anaisabel.morales@mi.infn.it |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-9007 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000341315100007 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1913 |
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| Author |
Kucuk, L. et al; Orrigo, S.E.A.; Montaner-Piza, A.; Rubio, B.; Gelletly, W.; Algora, A.; Molina, F. |
| Title |
Half-life determination of T-z =-1 and T-z =-1/2 proton-rich nuclei and the beta decay of Zn-58 |
Type |
Journal Article |
| Year |
2017 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
| Volume |
53 |
Issue |
6 |
Pages |
134 - 10pp |
| Keywords |
|
| Abstract |
We have measured the beta-decay half-lives of 16 neutron-deficient nuclei with T-z = -1/2 and -1, ranging from chromium to germanium. They were produced in an experiment carried out at GANIL and optimized for the production of Zn-58, for which in addition we present the decay scheme and absolute Fermi and Gamow-Teller transition strengths. Since all of these nuclei lie on the rp-process pathway, the T-1/2 values are important ingredients for the rp-process reaction flow calculations and for models of X-ray bursters. |
| Address |
[Kucuk, L.; Oktem, Y.; Cakirli, R. B.; Ganioglu, E.; Susoy, G.] Istanbul Univ, Dept Phys, TR-34134 Istanbul, Turkey, Email: sonja.orrigo@ific.uv.es; |
| Corporate Author |
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Thesis |
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| Publisher |
Springer |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1434-6001 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000404286000003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3189 |
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| Author |
Karakoc, M. et al; Molina, F. |
| Title |
Gamow-Teller transitions in the A=40 isoquintet of relevance for neutrino captures in Ar-40 |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
89 |
Issue |
6 |
Pages |
064313 - 7pp |
| Keywords |
|
| Abstract |
Background: The Gamow-Teller response of Ar-40 is important for the use of liquid argon as a medium for neutrino detection. An ambiguity about the Gamow-Teller strength for the excitation of 1(+) states at 2290 and 2730 keV in K-40 results in a significant uncertainty for neutrino capture rates. This ambiguity is caused by the large discrepancy observed between strengths extracted from Ar-40(p, n) charge-exchange data and the transition strengths for the analog transitions studied in the beta decay of Ti-40. Purpose: This study was aimed at resolving the ambiguity between the results from the Ar-40(p, n) charge-exchange and Ti-40 beta-decay data. Method: Shell-model calculations in the sd-pf shell with a new interaction (WBMB-C) were used to study differences between the structure of the transitions from Ar-40 and Ti-40. Distorted-wave Born approximation reaction calculations were used to investigate uncertainties in the extraction of Gamow-Teller strength from the Ar-40(p, n) data. New high-resolution data for the Ar-40(He-3,t) reaction were used to gain further insight into the charge-exchange reaction mechanism and to provide more information to test the validity of the shell-model calculations. Results: The shell-model calculations showed that interference between amplitudes associated with pf and sd components to the low-lying Gamow-Teller transitions, in combination with a difference in Coulomb energy shifts for Ar-40 and Ti-40, can produce the differences on the scale of those observed between the Ar-40 charge-exchange and Ti-40 beta-decay data. In combination with the difference in nuclear penetrability of the (p, n) and (He-3,t) probes, the different contributions from amplitudes associated with transitions in the pf and sd shells are likely also responsible for the observed discrepancy between the ratio of the cross sections for the low-lying 1(+) states in the Ar-40(p, n) and Ar-40(He-3,t) data. Conclusions: On the basis of this study, it is recommended to use Gamow-Teller strengths extracted from the Ar-40(p, n) data, not the Ti-40 beta-decay data, for the calculation of neutrino capture rates. Further theoretical studies are required to achieve a consistent quantitative description for the energy differences between low-lying 1(+) states in K-40 and Sc-40 and the experimentally observed Gamow-Teller strengths. |
| Address |
[Karakoc, M.; Boztosun, I.] Akdeniz Univ, Dept Phys, TR-07058 Antalya, Turkey, Email: zegers@nscl.msu.edu |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0556-2813 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
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Conference |
|
| Notes |
WOS:000338641500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1851 |
| Permanent link to this record |
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| Author |
Fujita, Y.; Rubio, B.; Adachi, T.; Blank, B.; Fujita, H.; Gelletly, W.; Molina, F.; Orrigo, S.E.A. |
| Title |
Gamow-Teller excitations studied by weak and strong interactions |
Type |
Journal Article |
| Year |
2015 |
Publication |
Acta Physica Polonica B |
Abbreviated Journal |
Acta Phys. Pol. B |
| Volume |
46 |
Issue |
3 |
Pages |
657-668 |
| Keywords |
|
| Abstract |
Studying weak nuclear responses, especially the Gamow-Teller (GT) transitions starting from stable as well as unstable nuclei, provide crucial and critical information on nuclear structure. Therefore, the study of GT transitions is a key issue in nuclear physics and also nuclear-astrophysics. Under the assumption of isospin symmetry, it is expected that the structure of mirror nuclei and the GT transitions starting from their ground states are identical. We have studied the corresponding GT transitions starting from T-z = +/- 1 and +/- 2 p f -shell nuclei, respectively, by means of hadronic (He-3,t) charge-exchange reactions and mirror beta decays. The results on GT strength distributions measured in beta decays and (He-3,t) reactions performed at an intermediate incident energy of 140 MeV/nucleon and 0 degrees are compared. The combined results help provide an understanding of nuclear structure of nuclei far-from-stability. |
| Address |
[Fujita, Y.; Adachi, T.; Fujita, H.] Osaka Univ, Nucl Phys Res Ctr, Ibaraki, Osaka 5670047, Japan |
| Corporate Author |
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Thesis |
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| Publisher |
Wydawnictwo Uniwersytetu Jagiellonskiego |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0587-4254 |
ISBN |
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Medium |
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| Area |
|
Expedition |
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Conference |
|
| Notes |
WOS:000353565500047 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2220 |
| Permanent link to this record |
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| Author |
Fujita, H. et al; Algora, A.; Estevez-Aguado, E.; Molina, F.; Rubio, B. |
| Title |
Experimental study of Gamow-Teller transitions via the high-energy-resolution O-18(He-3, t)F-18 reaction: Identification of the low-energy “super” -Gamow-Teller state |
Type |
Journal Article |
| Year |
2019 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
100 |
Issue |
3 |
Pages |
034618 - 13pp |
| Keywords |
|
| Abstract |
Using the high-resolution O-18(He-3, t)F-18 reaction at 0 degrees and at 140 MeV/nucleon, Gamow-Teller (GT) transitions were studied. A high energy resolution of 31 keV was achieved by applying dispersion matching techniques. The main part of the observed GT transition strength is concentrated in the transition to the F-18 ground state (g.s.). The absolute values of the reduced GT transition strengths, B(GT), were derived up to E-x = 12 MeV assuming proportionality between the B(GT) values and the reaction cross sections at 0 degrees. The B(GT) value obtained from the beta decay of F-18 (g.s.) -> O-18 (g.s.) was used to determine the proportionality constant. A total B(GT) of 4.06(5) was found and 76(1)% of the strength is concentrated to the ground state of F-18. The obtained B(GT) values were compared with those from the O-18(p, n) F-18 reaction and the mirror symmetric beta(+) decay of Ne-18 -> F-18. The candidates for 1(+) states with isospin T = 1 were identified by comparison with the O-18(p, p') data. The results of shell-model and quasiparticle-random-phase approximation calculations suggest constructive contributions of various configurations to the F-18 ground state, suggesting that this state is the low-energy super GT state. |
| Address |
[Fujita, H.; Fujita, Y.; Adachi, T.; Hatanaka, K.; Hirota, K.; Ishikawa, D.; Matsubara, H.; Okamura, H.; Ong, H. J.; Susoy, G.; Suzuki, T.; Tamii, A.; Zenihiro, J.] Osaka Univ, Res Ctr Nucl Phys, Ibaraki, Osaka 5670047, Japan, Email: hfujita@rcnp.osaka-u.ac.jp |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
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Medium |
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| Area |
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Expedition |
|
Conference |
|
| Notes |
WOS:000488259800004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4165 |
| Permanent link to this record |
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| |
| Author |
Molina, F.; Aguilera, P.; Romero-Barrientos, J.; Arellano, H.F.; Agramunt, J.; Medel, J.; Morales, J.R.; Zambra, M. |
| Title |
Energy distribution of the neutron flux measurements at the Chilean Reactor RECH-1 using multi-foil neutron activation and the Expectation Maximization unfolding algorithm |
Type |
Journal Article |
| Year |
2017 |
Publication |
Applied Radiation and Isotopes |
Abbreviated Journal |
Appl. Radiat. Isot. |
| Volume |
129 |
Issue |
|
Pages |
28-34 |
| Keywords |
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| Abstract |
We present a methodology to obtain the energy distribution of the neutron flux of an experimental nuclear reactor, using multi-foil activation measurements and the Expectation Maximization unfolding algorithm, which is presented as an alternative to well known unfolding methods such as GRAVEL. Self-shielding flux corrections for energy bin groups were obtained using MCNP6 Monte Carlo simulations. We have made studies at the at the Dry Tube of RECH-1 obtaining fluxes of 1.5(4) x 10(13) cm(-2) s(-1) for the thermal neutron energy region, 1.9(5) x 10(12) cm(-2) s(-1) for the epithermal neutron energy region, and 4.3(11) x 10(11) cm(-2) s(-1) for the fast neutron energy region. |
| Address |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
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Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0969-8043 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000413058200005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3326 |
| Permanent link to this record |
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| Author |
Romero-Barrientos, J.; Marquez Damian, J.I.; Molina, F.; Zambra, M.; Aguilera, P.; Lopez-Usquiano, F.; Parra, B.; Ruiz, A. |
| Title |
Calculation of kinetic parameters beta eff and L with modified open source Monte Carlo code OpenMC(TD) |
Type |
Journal Article |
| Year |
2022 |
Publication |
Nuclear Engineering and Technology |
Abbreviated Journal |
Nucl. Eng. Technol. |
| Volume |
54 |
Issue |
3 |
Pages |
811-816 |
| Keywords |
OpenMC; Monte Carlo; Kinetic parameters; Open source; Neutron generation time; Effective delayed neutron fraction |
| Abstract |
This work presents the methodology used to expand the capabilities of the Monte Carlo code OpenMC for the calculation of reactor kinetic parameters: effective delayed neutron fraction beff and neutron generation time L. The modified code, OpenMC(Time-Dependent) or OpenMC(TD), was then used to calculate the effective delayed neutron fraction by using the prompt method, while the neutron generation time was estimated using the pulsed method, fitting L to the decay of the neutron population. OpenMC(TD) is intended to serve as an alternative for the estimation of kinetic parameters when licensed codes are not available. The results obtained are compared to experimental data and MCNP calculated values for 18 benchmark configurations. |
| Address |
[Romero-Barrientos, J.; Molina, F.; Zambra, M.; Aguilera, P.; Lopez-Usquiano, F.; Ruiz, A.] Comis Chilena Energia Nucl, Santiago 12501, Chile, Email: romeroj@uchile.cl |
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Thesis |
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| Publisher |
Korean Nuclear Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1738-5733 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000766649800004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5172 |
| Permanent link to this record |
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| Author |
Morales, A.I. et al; Algora, A.; Molina, F.; Rubio, B. |
| Title |
beta-delayed gamma-ray spectroscopy of Au-203,Au-204 and Pt200-202 |
Type |
Journal Article |
| Year |
2013 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
88 |
Issue |
1 |
Pages |
014319 - 12pp |
| Keywords |
|
| Abstract |
The beta decay of five heavy, neutron-rich nuclei, Pt-203,Pt-204 and Ir200-202, has been investigated following relativistic cold fragmentation reactions of lead projectiles using the FRS + RISING setup at GSI. This paper reports on the study of the low-lying states in the decay daughter nuclei Au-203,Au-204 and Pt200-202. The characteristic gamma rays for each nucleus have been determined using beta-delayed gamma-ray spectroscopy. Tentative level schemes, relative intensities, and apparent beta feedings are provided. These data are compared with shell-model calculations, which indicate a substantial contribution to the total beta strength from high-energy first-forbidden beta-decay transitions in this mass region. |
| Address |
[Morales, A. I.; Benlliure, J.; Verma, S.; Casarejos, E.; Alvarez-Pol, H.; Estevez-Aguado, M. E.] Univ Santiago de Compostela, E-15782 Santiago De Compostela, Spain, Email: anaisabel.morales@mi.infn.it |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0556-2813 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000322113600003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1527 |
| Permanent link to this record |
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| Author |
Rubio, B. et al; Orrigo, S.E.A.; Montaner-Piza, A.; Agramunt, J.; Algora, A.; Molina, F. |
| Title |
Beta Decay Study of the T-z =-2 Zn-56 Nucleus and the Determination of the Half-Lives of a Few fp-shell Nuclei |
Type |
Journal Article |
| Year |
2014 |
Publication |
Nuclear Data Sheets |
Abbreviated Journal |
Nucl. Data Sheets |
| Volume |
120 |
Issue |
|
Pages |
37-40 |
| Keywords |
|
| Abstract |
This paper concerns the experimental study of the beta decay properties of few proton-rich fp-shell nuclei. The nuclei were produced at GANIL in fragmentation reactions, separated with the LISE spectrometer and stopped in an implantation detector surrounded by Ge detectors. The beta-delayed gammas, beta-delayed protons and the exotic beta-delayed gamma-proton emission have been studied. Preliminary results are presented. The decay of the T-z = -2 nucleus Zn-56 has been studied in detail. Information from the beta-delayed protons and beta-delayed gammas has been used to deduce the decay scheme. The exotic beta-delayed gamma-proton decay has been observed for the first time in the fp-shell. The interpretation of the data was made possible thanks to the detailed knowledge of the mirror Charge Exchange (CE) process and the gamma de-excitation of the states in Co-56, the mirror nucleus of Cu-56. |
| Address |
[Rubio, B.; Orrigo, S. E. A.; Montaner-Piza, A.; Agramunt, J.; Algora, A.; Molina, F.] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: Berta.Rubio@ific.uv.es |
| Corporate Author |
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Thesis |
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| Publisher |
Academic Press Inc Elsevier Science |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0090-3752 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000339860100010 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1870 |
| Permanent link to this record |
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| Author |
Orrigo, S.E.A. et al; Rubio, B.; Gelletly, W.; Agramunt, J.; Algora, A.; Molina, F. |
| Title |
beta decay of the exotic T-z =-2 nuclei Fe-48, Ni-52, and Zn-56 |
Type |
Journal Article |
| Year |
2016 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
93 |
Issue |
4 |
Pages |
044336 - 18pp |
| Keywords |
|
| Abstract |
The results of a study of the beta decays of three proton-rich nuclei with T-z = -2, namely Fe-48, Ni-52, and Zn-56, produced in an experiment carried out at GANIL, are reported. In all three cases we have extracted the half-lives and the total beta-delayed proton emission branching ratios. We have measured the individual beta-delayed protons and beta-delayed. rays and the branching ratios of the corresponding levels. Decay schemes have been determined for the three nuclei, and new energy levels are identified in the daughter nuclei. Competition between beta-delayed protons and. rays is observed in the de-excitation of the T = 2 isobaric analog states in all three cases. Absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. In addition, we discuss in detail the data analysis taking as a test case Zn-56, where the exotic beta-delayed gamma-proton decay has been observed. |
| Address |
[Orrigo, S. E. A.; Rubio, B.; Gelletly, W.; Agramunt, J.; Algora, A.; Molina, F.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: sonja.orrigo@ific.uv.es |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000374955500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2645 |
| Permanent link to this record |
