Records |
Author |
n_TOF Collaboration (Mendoza, E. et al); Domingo-Pardo, C.; Tain, J.L. |
Title |
Measurement and analysis of the Am-243 neutron capture cross section at the n_TOF facility at CERN |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
90 |
Issue |
3 |
Pages |
034608 - 16pp |
Keywords |
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Abstract |
Background: The design of new nuclear reactors and transmutation devices requires to reduce the present neutron cross section uncertainties of minor actinides. Purpose: Improvement of the Am-243(n, gamma) cross section uncertainty. Method: The Am-243(n, gamma) cross section has been measured at the n_TOF facility at CERN with a BaF2 total absorption calorimeter, in the energy range between 0.7 eV and 2.5 keV. Results: The Am-243(n, gamma) cross section has been successfully measured in the mentioned energy range. The resolved resonance region has been extended from 250 eV up to 400 eV. In the unresolved resonance region our results are compatible with one of the two incompatible capture data sets available below 2.5 keV. The data available in EXFOR and in the literature have been used to perform a simple analysis above 2.5 keV. Conclusions: The results of this measurement contribute to reduce the Am-243(n, gamma) cross section uncertainty and suggest that this cross section is underestimated up to 25% in the neutron energy range between 50 eV and a few keV in the present evaluated data libraries. |
Address |
[Mendoza, E.; Cano-Ott, D.; Guerrero, C.; Alvarez-Velarde, F.; Balibrea, J.; Gonzalez-Romero, E.; Martinez, T.; Villamarin, D.; Vicente, M. C.] CIEMAT, E-28040 Madrid, Spain |
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:000341912100005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1935 |
Permanent link to this record |
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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 |
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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 |
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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: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 |
Xie, J.J.; Wang, E.; Nieves, J. |
Title |
Re-analysis of the A(1520) photoproduction reaction |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
89 |
Issue |
1 |
Pages |
015203 - 10pp |
Keywords |
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Abstract |
Based on previous studies that support the important role of the N*(2120)D-13 resonance in the gamma p -> K+ A(1520) reaction, we make a re-analysis of this A(1520) photoproduction reaction taking into account the recent CLAS differential cross-section data. In addition to the contact, t-channel (K) over bar exchange, s-channel nucleon pole, and N*(2120) [previously called N*(2080)] resonance contributions, which have been considered in previous works, we also study the u-channel A(1115) hyperon pole term. The latter mechanism has always been ignored in all theoretical analysis, which has mostly relied on the very forward K+ angular LEPS data. It is shown that when the contributions from the N*(2120) resonance and the A(1115) hyperon are taken into account, both the new CLAS and the previous LEPS data can be simultaneously described. We also show that the contribution from the u-channel A(1115) pole term produces an enhancement for large K+ angles, and it becomes more and more relevant as the photon energy increases, being essential to describe the CLAS differential cross sections at backward angles. Furthermore, we find that the new CLAS data also favor the existence of the N*(2120) resonance and that these measurements can be used to further constrain its properties. |
Address |
[Xie, Ju-Jun] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China, Email: xiejujun@impcas.ac.cn; |
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:000332160300009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1718 |
Permanent link to this record |
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Author |
Sarriguren, P.; Algora, A.; Pereira, J. |
Title |
Gamow-Teller response in deformed even and odd neutron-rich Zr and Mo isotopes |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
89 |
Issue |
3 |
Pages |
034311 - 13pp |
Keywords |
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Abstract |
beta-decay properties of neutron-rich Zr and Mo isotopes are investigated within a microscopic theoretical approach based on the proton-neutron quasiparticle random-phase approximation. The underlying mean field is described self-consistently from deformed Skyrme Hartree-Fock calculations with pairing correlations. Residual separable particle-hole and particle-particle forces are also included in the formalism. The structural evolution in these isotopic chains including both even and odd isotopes is analyzed in terms of the equilibrium deformed shapes. Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron-emission probabilities are studied, stressing their relevance to describe the path of the nucleosynthesis rapid neutron capture process. |
Address |
[Sarriguren, P.] CSIC, Inst Estruct Mat, IEM, E-28006 Madrid, Spain, Email: p.sarriguren@csic.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 |
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:000334123900005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1762 |
Permanent link to this record |
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Author |
Martinez, T. et al; Agramunt, J.; Algora, A.; Domingo-Pardo, C.; Jordan, M.D.; Rubio, B.; Tain, J.L. |
Title |
MONSTER: a TOF Spectrometer for beta-delayed Neutron Spectroscopy |
Type |
Journal Article |
Year |
2014 |
Publication |
Nuclear Data Sheets |
Abbreviated Journal |
Nucl. Data Sheets |
Volume |
120 |
Issue |
|
Pages |
78-80 |
Keywords |
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Abstract |
beta-delayed neutron (DN) data, including emission probabilities, P-n, and energy spectrum, play an important role in our understanding of nuclear structure, nuclear astrophysics and nuclear technologies. A MOdular Neutron time-of-flight SpectromeTER (MONSTER) is being built for the measurement of the neutron energy spectra and branching ratios. The TOF spectrometer will consist of one hundred liquid scintillator cells covering a significant solid angle. The MONSTER design has been optimized by using Monte Carlo (MC) techniques. The response function of the MONSTER cell has been characterized with mono-energetic neutron beams and compared to dedicated MC simulations. |
Address |
[Martinez, T.; Cano-Ott, D.; Castilla, J.; Garcia, A. R.; Marin, J.; Martinez, G.; Mendoza, E.; Santos, C.; Tera, F. J.; Villamarin, D.] CIEMAT, Ctr Invest Energet, Medio Ambient Tecnol, E-28040 Madrid, Spain, Email: trino.martinez@ciemat.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:000339860100021 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1872 |
Permanent link to this record |