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Author n_TOF Collaboration (Guerrero, C. et al); Giubrone, G.; Tain, J.L.
Title Characterization of the New n_TOF Neutron Beam: Fluence, Profile and Resolution Type Journal Article
Year 2011 Publication Journal of the Korean Physical Society Abbreviated Journal J. Korean Phys. Soc.
Volume 59 Issue 2 Pages 1624-1627
Keywords n_TOF; Time-of-flight; Neutron beam; Nuclear data; Cross sections
Abstract After a halt of four years, the nTOF spallation neutron facility at CERN has resumed operation in November 2008 with a new spallation target characterized by an improved safety and engineering design, resulting in a more robust overall performance and efficient cooling. The first measurement during the 2009 run has aimed at the full characterization of the neutron beam. Several detectors, such as calibrated fission chambers, the nTOF Silicon Monitor, a MicroMegas detector with (10)B and (235)U samples, as well as liquid and solid scintillators have been used in order to characterize the properties of the neutron fluence. The spatial profile of the beam has been studied with a specially designed “X-Y” MicroMegas which provided a 2D image of the beam as a function of neutron energy. Both properties have been compared with simulations performed. with the FLUKA code. The characterization of the resolution function is based on results from simulations which have been verified by the study of narrow capture resonances. of (56)Fe, which were measured as part of a new campaign of (n,gamma) measurements on Fe and Ni isotopes.
Address [Guerrero, C; Becares, V; Cano-Ott, D; Fernandez-Ordonez, M; Gonzalez-Romero, E; Martin-Fuertes, F; Martinez, T; Mendoza, E; Pina, G; Quinones, J; Vlachoudis, V] Ctr Invest Energet Medioambientales & Tecnol, Madrid 28040, Spain, Email: carlos.guerrero@ciemat.es
Corporate Author Thesis
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:000294080700041 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 735
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Author n_TOF Collaboration (Guerrero, C. et al); Domingo-Pardo, C.; Tain, J.L.
Title Study of Photon Strength Function of Actinides: the Case of (235)U, (238)Np and (241)Pu Type Journal Article
Year 2011 Publication Journal of the Korean Physical Society Abbreviated Journal J. Korean Phys. Soc.
Volume 59 Issue 2 Pages 1510-1513
Keywords Photon/Gamma strength functions; Pygmy; Scissor mode; n_TOF; Total absorption calorimeter; TAC; Neutron capture
Abstract The decay from excited levels in medium and heavy nuclei can be described in a statistical approach by means of Photon Strength Functions and Level Density distributions. The study of electromagnetic cascades following neutron capture based on the use of high efficiency detectors has been shown to be well suited for probing the properties of the Photon Strength Function of heavy (high level density) and/or radioactive (high background) nuclei. In this work we have investigated for the first time the validity of the recommended PSF of actinides, in particular (235)U, (238)Np and (241)Pu. Our study includes the search for resonance structures in the PSF below S(n) and draws conclusions regarding their existence and their characteristics in terms of energy, width and electromagnetic nature.
Address [Guerrero, C; Alvarez-Velarde, F; Ano-Ott, DC; Martinez, T; Mendoza, E; Villamarin, D] Ctr Invest Energet Medioambientales & Technol CIE, Madrid, Spain, Email: carlos.guerrero@ciemat.es
Corporate Author Thesis
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:000294080700013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 731
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Author Guerrero, C.; Domingo-Pardo, C.; Kappeler, F.; Lerendegui-Marco, J.; Palomo, F.R.; Quesada, J.M.; Reifarth, R.
Title Prospects for direct neutron capture measurements on s-process branching point isotopes Type Journal Article
Year 2017 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 53 Issue 5 Pages 87 - 5pp
Keywords
Abstract The neutron capture cross sections of several unstable key isotopes acting as branching points in the s-process are crucial for stellar nucleosynthesis studies, but they are very challenging to measure directly due to the difficult production of sufficient sample material, the high activity of the resulting samples, and the actual (n, gamma) measurement, where high neutron fluxes and effective background rejection capabilities are required. At present there are about 21 relevant s-process branching point isotopes whose cross section could not be measured yet over the neutron energy range of interest for astrophysics. However, the situation is changing with some very recent developments and upcoming technologies. This work introduces three techniques that will change the current paradigm in the field: the use of gamma-ray imaging techniques in (n,gamma) experiments, the production of moderated neutron beams using high-power lasers, and double capture experiments in Maxwellian neutron beams.
Address [Guerrero, C.; Lerendegui-Marco, J.; Quesada, J. M.] Univ Seville, Dept Fis Atom Mol & Nucl, E-41012 Seville, Spain, Email: carlos.guerrero@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000400982700002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3129
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Author n_TOF Collaboration (Guerrero, C. et al); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L.
Title Performance of the neutron time-of-flight facility n_TOF at CERN Type Journal Article
Year 2013 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 49 Issue 2 Pages 27 - 15pp
Keywords
Abstract The neutron time-of-flight facility n_TOF features a white neutron source produced by spallation through 20 GeV/c protons impinging on a lead target. The facility, aiming primarily at the measurement of neutron-induced reaction cross sections, was operating at CERN between 2001 and 2004, and then underwent a major upgrade in 2008. This paper presents in detail all the characteristics of the new neutron beam in the currently available configurations, which correspond to two different collimation systems and two choices of neutron moderator. The characteristics discussed include the intensity and energy dependence of the neutron flux, the spatial profile of the beam, the in-beam background components and the energy resolution/broadening. The discussion of these features is based on dedicated measurements and Monte Carlo simulations, and includes estimations of the systematic uncertainties of the mentioned quantities.
Address [Guerrero, C.; Tsinganis, A.; Berthoumieux, E.; Weiss, C.; Chiaveri, E.; Calviani, M.; Vlachoudis, V.; Andriamonje, S.; Boccone, V.; Brugger, M.; Cerutti, F.; Chin, M.; Ferrari, A.; Hernandez-Prieto, A.; Kadi, Y.; Losito, R.; Roman, F.; Rubbia, C.; Versaci, R.] CERN, European Org Nucl Res, CH-1211 Geneva, Switzerland, Email: carlos.guerrero@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000315601600011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1358
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Author n_TOF Collaboration (Guerrero, C. et al); Giubrone, G.; Tain, J.L.
Title Simultaneous measurement of neutron-induced capture and fission reactions at CERN Type Journal Article
Year 2012 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 48 Issue 3 Pages 29 - 9pp
Keywords
Abstract The measurement of the capture cross-section of fissile elements, of utmost importance for the design of innovative nuclear reactors and the management of nuclear waste, faces particular difficulties related to the.-ray background generated in the competing fission reactions. At the CERN neutron time-of-flight facility nTOF we have combined the Total Absorption Calorimeter (TAC) capture detector with a set of three U-235 loaded MicroMegas (MGAS) fission detectors for measuring simultaneously two reactions: capture and fission. The results presented here include the determination of the three detection efficiencies involved in the process: epsilon(TAC)(n, f), epsilon(TAC)(n, gamma) and epsilon(MGAS)(n, f). In the test measurement we have succeeded in measuring simultaneously with a high total efficiency the U-235 capture and fission cross-sections, disentangling accurately the two types of reactions. The work presented here proves that accurate capture cross-section measurements of fissile isotopes are feasible at nTOF.
Address [Guerrero, C.; Berthoumieux, E.; Andriamonje, S.; Brugger, M.; Calviani, M.; Cerutti, F.; Chiaveri, E.; Chin, M.; Ferrari, A.; Kadi, Y.; Lebbos, E.; Losito, R.; Roman, F.; Rubbia, C.; Tsinganis, A.; Vlachoudis, V.] European Org Nucl Res CERN, Geneva, Switzerland, Email: carlos.guerrero@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000303537100013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1017
Permanent link to this record