Records |
Author |
n_TOF Collaboration (Cosentino, L. et al); Domingo-Pardo, C.; Tain, J.L.; Tarifeño-Saldivia, A. |
Title |
Experimental setup and procedure for the measurement of the Be-7(n,alpha)alpha reaction at n_TOF |
Type |
Journal Article |
Year |
2016 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
830 |
Issue |
|
Pages |
197-205 |
Keywords |
Cosmological lithium problem; Big bang nucleosynthesis; Be-7(n,alpha)alpha reaction; n_TOF spallation neutron source |
Abstract |
The newly built second experimental area EAR2 of then n_ToF spallation neutron source at CERN allows to perform (n, charged particles) experiments on short-lived highly radioactive targets. This paper describes a detection apparatus and the experimental procedure for the determination of the cross-section of the Be-7(n,alpha)alpha reaction, which represents one of the focal points toward the solution of the cosmological Lithium abundance problem, and whose only measurement, at thermal energy, dates back to 1963. The apparently unsurmountable experimental difficulties stemming from the huge Be-7 gamma-activity, along with the lack of a suitable neutron beam facility, had so far prevented further measurements. The detection system is subject to considerable radiation damage, but is capable of disentangling the rare reaction signals from the very high background. This newly developed setup could likely be useful also to study other challenging reactions requiring the detectors to be installed directly in the neutron beam. |
Address |
[Cosentino, L.; Musumarra, A.; Pappalardo, A.; Piscopo, M.; Finocchiaro, P.; Cardella, R.; Heyse, J.; Jenkins, D. G.; Kaeppeler, F.; Katabuchi, T.; Kokkoris, M.; Lederer, C.; Lonsdale, S.; Massimi, C.; Mastinu, P.; Matteucci, F.; Mazzone, A.; Milazzo, P. M.; Nolte, R.; Patronis, N.; Pavlik, A.; Rauscher, T.; Schillebeeckx, P.; Stamatopoulos, A.; Tsinganis, A.; Vannini, G.; Vlastou, R.; Wallner, A.; Woods, P. J.] INFN Lab Nazl Sud, Catania, Italy, Email: FINOCCHIARO@LNS.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 |
|
Series Issue |
|
Edition |
|
ISSN |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000381530300027 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2792 |
Permanent link to this record |
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Author |
n_TOF Collaboration (Zugec, P. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L. |
Title |
GEANT4 simulation of the neutron background of the C6D6 set-up for capture studies at n_TOF |
Type |
Journal Article |
Year |
2014 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
760 |
Issue |
|
Pages |
57-67 |
Keywords |
GEANT4 simulations; Neutron time of flight; Neutron background; N_TOF; Neutron capture |
Abstract |
The neutron sensitivity of the Cr6D6 detector setup used at nTOF facility for capture measurements has been studied by means of detailed GEANT4 simulations. A realistic software replica of the entire nTOF experimental hall, including the neutron beam line, sample, detector supports and the walls of the experimental area has been implemented in the simulations. The simulations have been analyzed in the same manner as experimental data, in particular by applying the Pulse Height Weighting Technique. The simulations have been validated against a measurement of the neutron background performed with a(nat)-C sample, showing an excellent agreement above 1 keV. At lower energies, an additional component in the measured C-nat yield has been discovered, which prevents the use of C-nat data for neutron background estimates at neutron energies below a few hundred eV. The origin and time structure of the neutron background have been derived from the simulations. Examples of the neutron background for two different samples are demonstrating the important role of accurate simulations of the neutron background in capture cross-section measurements. |
Address |
[Zugec, P.; Bosnar, D.] Univ Zagreb, Fac Sci, Dept Phys, Zagreb 41000, Croatia, Email: pzugec@phy.hr |
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 |
|
Edition |
|
ISSN |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000338350500008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1828 |
Permanent link to this record |
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Author |
n_TOF Collaboration (Calviani, M. et al); Domingo-Pardo, C.; Tain, J.L. |
Title |
Fission Cross-section Measurements of (233)U, (245)Cm and (241,243)Am at CERN n_TOF Facility |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of the Korean Physical Society |
Abbreviated Journal |
J. Korean Phys. Soc. |
Volume |
59 |
Issue |
2 |
Pages |
1912-1915 |
Keywords |
ND2010; Nuclear data; ENDF; n_TOF; Neutron-induced fission reactions; Am; Cm; U |
Abstract |
Neutron-induced fission cross-sections of minor actinides have been measured using the nTOF white neutron source at CERN. Geneva, as part of a large experimental program aiming at collecting new data relevant for nuclear astrophysics and for the design of advanced reactor systems. The measurements at nTOF take advantage of the innovative features of the n_TOF facility, namely the wide energy range, high instantaneous neutron flux and good energy resolution. Final results on the fission cross-section of (233)U, (245)cm and (243)Am from thermal to 20 MeV are here reported, together with preliminary results for (241)Am. The measurement have been performed with a dedicated Fast Ionization Chamber (FIC), a fission fragment detector with a very high efficiency, relative to the very well known cross-section of (235)U, measured simultaneously with the same detector. |
Address |
[Calviani, M; Andriamonje, S; Chiaveri, E; Vlachoudis, V] CERN, Geneva, Switzerland, Email: marco.calviani@cern.ch |
Corporate Author |
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Thesis |
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Publisher |
Korean 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 |
|
Series Issue |
|
Edition |
|
ISSN |
0374-4884 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000294080700111 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
741 |
Permanent link to this record |
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Author |
n_TOF Collaboration (Paradela, C. et al); Domingo-Pardo, C.; Plag, R.; Plompen, A.; Tain, J.L. |
Title |
(237)Np(n,f) Cross Section: New Data and Present Status |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of the Korean Physical Society |
Abbreviated Journal |
J. Korean Phys. Soc. |
Volume |
59 |
Issue |
2 |
Pages |
1908-1911 |
Keywords |
Nuclear data; Neutron-induced fission reactions; Np-237; n_TOF experiment |
Abstract |
In this document, we present the final result obtained at the nTOF experiment; for the neutron-induced fission cross section of the (237)Np, from the fission threshold up to 1 GeV. The method applied to get tins result is briefly discussed. nTOF data are compared to the last experimental measurements using other TOF facilities or the surrogate method, reported experiments performed with monoenergetic sources and the FISCAL systematic, including a discussion about the existing discrepancies. |
Address |
[Paradela, C] Univ Santiago de Compostela, Fac Fis, Santiago De Compostela 15782, Spain, Email: carlos.paradela@usc.es |
Corporate Author |
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Thesis |
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Publisher |
Korean 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 |
|
ISSN |
0374-4884 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000294080700110 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
740 |
Permanent link to this record |
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|
|
Author |
n_TOF Collaboration (Tarrio, D. et al); Domingo-Pardo, C.; Plag, R.; Plompen, A.; Tain, J.L. |
Title |
High-energy Neutron-induced Fission Cross Sections of Natural Lead and Bismuth-209 |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of the Korean Physical Society |
Abbreviated Journal |
J. Korean Phys. Soc. |
Volume |
59 |
Issue |
2 |
Pages |
1904-1907 |
Keywords |
Nuclear data; Neutron-induced fission reactions; Pb-nat(n,f); Bi-209(n,f); Spallation neutron source; n_TOF facility |
Abstract |
The CERN Neutron Time-Of-Flight (n_TOF) facility is well suited to measure small neutron-induced fission cross sections, as those of subactinides. The cross section ratios of (nat)Pb and (209)Bi relative to (235)U and (238)U were measured using PPAC detectors. The fragment coincidence method allows to unambiguously identify the fission events. The present experiment provides the first results for neutron-induced fission up to 1 GeV for (nat)Pb and (209)Bi. A good agreement with previous experimental data below 200 MeV is shown. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross section is close to 1 GeV. |
Address |
[Tarrio, D] Univ Santiago de Compostela, Fac Fis, Santiago De Compostela 15782, Spain, Email: diego.tarrio@usc.es |
Corporate Author |
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Thesis |
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Publisher |
Korean 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 |
0374-4884 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000294080700109 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
739 |
Permanent link to this record |