| Records |
| Author |
n_TOF Collaboration (Massimi, C. et al.); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L. |
| Title |
Neutron spectroscopy of Mg-26 states: Constraining the stellar neutron source Ne-22(alpha, n)Mg-25 |
Type |
Journal Article |
| Year |
2017 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
768 |
Issue |
|
Pages |
1-6 |
| Keywords |
s Process; alpha+Ne-22; Neutron spectroscopy |
| Abstract |
This work reports on accurate, high-resolution measurements of the Mg-25(n, gamma)Mg-26 and Mg-25(n, tot) cross sections in the neutron energy range from thermal to about 300 keV, leading to a significantly improved Mg-25(n, gamma)Mg-26 parametrization. The relevant resonances for n+Mg-25 were characterized from a combined R-matrix analysis of the experimental data. This resulted in an unambiguous spin/parity assignment of the corresponding excited states in Mg-26. With this information experimental upper limits of the reaction rates for Ne-22(alpha, n)Mg-25 and Ne-22(alpha, gamma)Mg-26 were established, potentially leading to a significantly higher (alpha, n)/(alpha, gamma) ratio than previously evaluated. The impact of these results has been studied for stellar models in the mass range 2 to 25 M-circle dot. (C) 2017 The Author(s). Published by Elsevier B.V. |
| Address |
[Massimi, C.; Barbagallo, M.; Becvar, F.; Bisterzok, S.; Castelluccio, D. M.; Eleftheriadis, C.; Finocchiaro, P.; Kokkoris, M.; Marganiec, J.; Plompen, A.; Praena, J.; Rubbia, C.; Weiss, C.] Ist Nazl Fis Nucl, Bologna, Italy, Email: cristian.massimi@bo.infn.it |
| Corporate Author |
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Thesis |
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Publisher  |
Elsevier Science Bv |
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 |
0370-2693 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000400677700001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3112 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Praena, J. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L.; Tarifeño-Saldivia, A. |
| Title |
Preparation and characterization of S-33 samples for S-33(n,alpha)Si-30 cross-section measurements at the n_TOF facility at CERN |
Type |
Journal Article |
| Year |
2018 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
| Volume |
890 |
Issue |
|
Pages |
142-147 |
| Keywords |
Neutron induced alpha emission; Thermal evaporation; Rutherford backscattering |
| Abstract |
Thin S-33 samples for the study of the S-33(n,alpha)Si-30 cross-section at the n_TOF facility at CERN were made by thermal evaporation of S-33 powder onto a dedicated substrate made of kapton covered with thin layers of copper, chromium and titanium. This method has provided for the first time bare sulfur samples a few centimeters in diameter. The samples have shown an excellent adherence with no mass loss after few years and no sublimation in vacuum at room temperature. The determination of the mass thickness of S-33 has been performed by means of Rutherford backscattering spectrometry. The samples have been successfully tested under neutron irradiation. |
| Address |
[Praena, J.; Porras, I.] Univ Granada, Granada, Spain, Email: jpraena@ugr.es |
| Corporate Author |
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Thesis |
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| Publisher |
Elsevier Science Bv |
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 |
0168-9002 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:000427814900020 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3537 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Calviani, M. et al); Giubrone, G.; Tain, J.L. |
| Title |
Neutron-induced fission cross section of Cm-245: New results from data taken at the time-of-flight facility n_TOF |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
85 |
Issue |
3 |
Pages |
034616 - 10pp |
| Keywords |
|
| Abstract |
The neutron-induced fission cross section of Cm-245 was measured at n_TOF in a wide energy range and with high resolution. The energy dependence, measured in a single measurement from 30 meV to 1 MeV neutron energy, has been determined with 5% accuracy relative to the U-235(n,f) cross section. In order to reduce the uncertainty on the absolute value, the data have been normalized at thermal energy to recent measurements performed at ILL and BR1. In the energy range of overlap, the results are in fair agreement with some previous measurements and confirm, on average, the evaluated cross section in the ENDF/B-VII.0 database, although sizable differences are observed for some important resonances below 20 eV. A similar behavior is observed relative to JENDL/AC-2008, a reactor-oriented database for actinides. The new results contribute to the overall improvement of the databases needed for the design of advanced reactor systems and may lead to refinements of fission models for the actinides. |
| Address |
[Calviani, M.; Gramegna, F.; Mastinu, P.; Sarchiapone, L.] Univ Padua, Ist Nazl Fis Nucl, Lab Nazl Legnaro, Padua, Italy, Email: marco.calviani@cern.ch |
| 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 |
|
| Notes |
WOS:000302105100004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
956 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Lederer, C. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L. |
| Title |
Neutron Capture Cross Section of Unstable Ni-63: Implications for Stellar Nucleosynthesis |
Type |
Journal Article |
| Year |
2013 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
110 |
Issue |
2 |
Pages |
022501 - 5pp |
| Keywords |
|
| Abstract |
The Ni-63(n, gamma) cross section has been measured for the first time at the neutron time-of-flight facility n_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian averaged cross sections were calculated for thermal energies from kT = 5-100 keV with uncertainties around 20%. Stellar model calculations for a 25M(circle dot) star show that the new data have a significant effect on the s-process production of Cu-63, Ni-64, and Zn-64 in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova. |
| Address |
[Lederer, C.; Paradela, C.; Wallner, A.] Univ Vienna, Fac Phys, A-1090 Vienna, Austria |
| 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 |
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| Notes |
WOS:000313336500005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1305 |
| Permanent link to this record |
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| Author |
n_TOF Collaboration (Lederer, C. et al.); Giubrone, G.; Tain, J.L. |
| Title |
Ni-62(n,gamma) and Ni-63(n,gamma) cross sections measured at the n_TOF facility at CERN |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
89 |
Issue |
2 |
Pages |
025810 - 11pp |
| Keywords |
|
| Abstract |
The cross section of the Ni-62(n,gamma) reaction was measured with the time-of-flight technique at the neutron time-of-flight facility nTOF at CERN. Capture kernels of 42 resonances were analyzed up to 200 keV neutron energy and Maxwellian averaged cross sections (MACS) from kT = 5-100 keV were calculated. With a total uncertainty of 4.5%, the stellar cross section is in excellent agreement with the the KADoNiS compilation at kT = 30 keV, while being systematically lower up to a factor of 1.6 at higher stellar temperatures. The cross section of the Ni-63(n,gamma) reaction was measured for the first time at nTOF. We determined unresolved cross sections from 10 to 270 keV with a systematic uncertainty of 17%. These results provide fundamental constraints on s-process production of heavier species, especially the production of Cu in massive stars, which serve as the dominant source of Cu in the solar system. |
| Address |
[Lederer, C.; Wallner, A.; Pavlik, A.] Univ Vienna, Fac Phys, A-1010 Vienna, Austria, Email: claudia.lederer@ph.ed.uk |
| 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:000332175500012 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1717 |
| Permanent link to this record |
