| Records |
| Author |
n_TOF Collaboration (Massimi, C. et al); Domingo-Pardo, C.; Tain, J.L. |
| Title |
Resonance neutron-capture cross sections of stable magnesium isotopes and their astrophysical implications |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
85 |
Issue |
4 |
Pages |
044615 - 15pp |
| Keywords |
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| Abstract |
We have measured the neutron capture cross sections of the stable magnesium isotopes Mg-24,Mg-25,Mg-26 in the energy range of interest to the s process using the neutron time-of-flight facility n_TOF at CERN. Capture events from a natural metal sample and from samples enriched in Mg-25 and Mg-26 were recorded using the total energy method based on (C6H6)-H-2 detectors. Neutron resonance parameters were extracted by a simultaneous resonance shape analysis of the present capture data and existing transmission data on a natural isotopic sample. Maxwellian-averaged capture cross sections for the three isotopes were calculated up to thermal energies of 100 keV and their impact on s-process analyses was investigated. At 30 keV the new values of the stellar cross section for Mg-24, Mg-25, and Mg-26 are 3.8 +/- 0.2 mb, 4.1 +/- 0.6 mb, and 0.14 +/- 0.01 mb, respectively. |
| Address |
[Massimi, C.; Vannini, G.] Univ Bologna, Dipartimento Fis, Bologna, Italy, Email: Cristian.Massimi@bo.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:000303069400003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
994 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Tagliente, G. et al.); Domingo-Pardo, C.; Tain, J.L. |
| Title |
(96)Zr(n,gamma) measurement at the n_TOF facility at CERN |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
84 |
Issue |
5 |
Pages |
055802 - 8pp |
| Keywords |
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| Abstract |
The (n,gamma) cross section of (96)Zr has been investigated at the CERN n_TOF spallation neutron source. High-resolution time-of-flight measurements using an enriched ZrO(2) sample allowed us to analyze 15 resonances below 40 keV with improved accuracy. On average, the capture widths were found to be 25% smaller than reported in earlier experiments. If complemented with the contribution by direct radiative capture, the derived Maxwellian averaged cross sections are consistent with activation data at kT = 25 keV. The present results confirm the astrophysical implications for the s-process branching at (95)Zr. |
| Address |
[Tagliente, G; Colonna, N; Marrone, S; Terlizzi, R] Ist Nazl Fis Nucl, I-70126 Bari, Italy, Email: giuseppe.tagliente@ba.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 |
|
| Notes |
WOS:000297121100005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
812 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Sarmento, R. et al); Domingo-Pardo, C.; Tain, J.L. |
| Title |
Measurement of the (236)U(n, f) cross section from 170 meV to 2 MeV at the CERN n_TOF facility |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
84 |
Issue |
4 |
Pages |
044618 - 10pp |
| Keywords |
|
| Abstract |
The neutron-induced fission cross section of (236)U was measured at the neutron Time-of-Flight (nTOF) facility at CERN relative to the standard (235)U(n, f) cross section for neutron energies ranging from above thermal to several MeV. The measurement, covering the full range simultaneously, was performed with a fast ionization chamber, taking advantage of the high resolution of the nTOF spectrometer. The n_TOF results confirm that the first resonance at 5.45 eV is largely overestimated in some nuclear data libraries. The resonance triplet around 1.2 keV was measured with high resolution and resonance parameters were determined with good accuracy. Resonances at high energy have also been observed and characterized and different values for the cross section are provided for the region between 10 keV and the fission threshold. The present work indicates various shortcomings of the current nuclear data libraries in the subthreshold region and provides the basis for an accurate re-evaluation of the (236)U(n, f) cross section, which is of great relevance for the development of emerging or innovative nuclear reactor technologies. |
| Address |
[Sarmento, R; Goncalves, IF; Vaz, P; Carrapico, C; de Albornoz, AC; Marques, L; Salgado, J; Tavora, L] ITN, Sacavem, Portugal |
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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 |
|
Expedition |
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Conference |
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| Notes |
WOS:000296521000006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
818 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Tagliente, G. et al.); Domingo-Pardo, C.; Tain, J.L. |
| Title |
Neutron capture on (94)Zr: Resonance parameters and Maxwellian-averaged cross sections |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
84 |
Issue |
1 |
Pages |
015801 - 9pp |
| Keywords |
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| Abstract |
The neutron capture cross sections of the Zr isotopes play an important role in nucleosynthesis studies. The s-process reaction flow between the Fe seed and the heavier isotopes passes through the neutron magic nucleus (90)Zr and through (91,92,93,94)Zr, but only part of the flow extends to (96)Zr because of the branching point at (95)Zr. Apart from their effect on the s-process flow, the comparably small isotopic (n, gamma) cross sections make Zr also an interesting structural material for nuclear reactors. The (94)Zr (n, gamma) cross section has been measured with high resolution at the spallation neutron source n_TOF at CERN and resonance parameters are reported up to 60 keV neutron energy. |
| Address |
[Tagliente, G; Colonna, N; Marrone, S; Terlizzi, R] Ist Nazl Fis Nucl, I-70126 Bari, Italy, Email: giuseppe.tagliente@ba.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 |
|
Conference |
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| Notes |
WOS:000292767200010 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
687 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Tarrio D. et al.); Domingo-Pardo, C.; Tain, J.L. |
| Title |
Neutron-induced fission cross section of Pb-nat and Bi-209 from threshold to 1 GeV: An improved parametrization |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
83 |
Issue |
4 |
Pages |
044620 - 9pp |
| Keywords |
|
| Abstract |
Neutron-induced fission cross sections for Pb-nat and Bi-209 were measured with a white-spectrum neutron source at the CERN Neutron Time-of-Flight (n_TOF) facility. The experiment, using neutrons from threshold up to 1 GeV, provides the first results for these nuclei above 200 MeV. The cross sections were measured relative to U-235 and U-238 in a dedicated fission chamber with parallel plate avalanche counter detectors. Results are compared with previous experimental data. Upgraded parametrizations of the cross sections are presented, from threshold energy up to 1 GeV. The proposed new sets of fitting parameters improve former results along the whole energy range. |
| Address |
[Tarrio, D.; Duran, I.; Paradela, C.] Univ Santiago de Compostela, Santiago De Compostela, Spain, Email: diego.tarrio@usc.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 |
|
| Area |
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Expedition |
|
Conference |
|
| Notes |
ISI:000290163300003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
617 |
| Permanent link to this record |
