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Author (up) Colonna, N.; Belloni, F.; Berthoumieux, E.; Calviani, M.; Domingo-Pardo, C.; Guerrero, C.; Karadimos, D.; Lederer, C.; Massimi, C.; Paradela, C.; Plag, R.; Praena, J.; Sarmento, R.
Title Advanced nuclear energy systems and the need of accurate nuclear data: the n_TOF project at CERN Type Journal Article
Year 2010 Publication Energy & Environmental Science Abbreviated Journal Energy Environ. Sci.
Volume 3 Issue 12 Pages 1910-1917
Keywords
Abstract To satisfy the world's constantly increasing demand for energy, a suitable mix of different energy sources has to be devised. In this scenario, an important role could be played by nuclear energy, provided that major safety, waste and proliferation issues affecting current nuclear reactors are satisfactorily addressed. To this purpose, a large effort has been under way for a few years towards the development of advanced nuclear systems with the aim of closing the fuel cycle. Generation IV reactors, with full or partial waste recycling capability, accelerator driven systems, as well as new fuel cycles are the main options being investigated. The design of advanced systems requires improvements in basic nuclear data, such as cross-sections for neutron-induced reactions on actinides. In this paper, the main concepts of advanced reactor systems are described, together with the related needs of new and accurate nuclear data. The present activity in this field at the neutron facility n_TOF at CERN is discussed.
Address [Colonna, N.] Ist Nazl Fis Nucl, Sez Bari, I-70126 Bari, Italy, Email: nicola.colonna@ba.infn.it
Corporate Author Thesis
Publisher Royal Soc Chemistry Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1754-5692 ISBN Medium
Area Expedition Conference
Notes ISI:000284590900007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 319
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Author (up) Guerrero, C.; Cano-Ott, D.; Mendoza, E.; Tain, J.L.; Algora, A.; Berthoumieux, E.; Colonna, N.; Domingo-Pardo, C.; Gonzalez-Romero, E.; Heil, M.; Jordan, D.; Kappeler, F.; Lampoudis, C.; Martinez, T.; Massimi, C.; Plag, R.
Title Monte Carlo simulation of the n_TOF Total Absorption Calorimeter Type Journal Article
Year 2012 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 671 Issue Pages 108-117
Keywords Monte Carlo simulation; Geant4; Neutron cross-sections; Time-of-flight; Neutron capture
Abstract The n_TOF Total Absorption Calorimeter (TAC) is a 4 pi BaF2 segmented detector used at CERN for measuring neutron capture cross-sections of importance for the design of advanced nuclear reactors. This work presents the simulation code that has been developed in GEANT4 for the accurate determination of the detection efficiency of the TAC for neutron capture events. The code allows to calculate the efficiency of the TAC for every neutron capture state, as a function of energy, crystal multiplicity, and counting rate. The code includes all instrumental effects such as the single crystal detection threshold and energy resolution, finite size of the coincidence time window, and signal pile-up. The results from the simulation have been validated with experimental data for a large set of electromagnetic de-excitation patterns: beta-decay of well known calibration sources, neutron capture reactions in light nuclei with well known level schemes like Ti-nat, reference samples used in (n,gamma) measurements like Au-197 and experimental data from an actinide sample like Pu-240. The systematic uncertainty in the determination of the detection efficiency has been estimated for all the cases. As a representative example, the accuracy reached for the case of Au-197(n,gamma) ranges between 0.5% and 2%, depending on the experimental and analysis conditions. Such a value matches the high accuracy required for the nuclear cross-section data needed in advanced reactor design.
Address [Guerrero, C.; Cano-Ott, D.; Mendoza, E.; Gonzalez-Romero, E.; Martinez, T.] CIEMAT, Ctr Invest Energet Medioambientales & Tecnol, E-28040 Madrid, Spain, Email: carlos.guerrero@cern.ch
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000301474600013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 973
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Author (up) Massimi, C.; Cristallo, S.; Domingo-Pardo, C.; Lederer-Woods, C.
Title n_TOF: Measurements of Key Reactions of Interest to AGB Stars Type Journal Article
Year 2022 Publication Universe Abbreviated Journal Universe
Volume 8 Issue 2 Pages 100 - 19pp
Keywords s process; MACS; time of flight
Abstract In the last 20 years, the neutron time-of-flight facility nTOF at CERN has been providing relevant data for the astrophysical slow neutron capture process (s process). At nTOF, neutron-induced radiative capture (n,gamma) as well as (n,p) and (n,alpha) reaction cross sections are measured as a function of energy, using the time-of-flight method. Improved detection systems, innovative ideas and collaborations with other neutron facilities have lead to a considerable contribution of the n_TOF collaboration to studying the s process in asymptotic giant branch stars. Results have been reported for stable and radioactive samples, i.e.,Mg- 24,Mg-25,Mg-26, Al-26, S-33,Fe- 54,Fe-57, Ni-58,Ni-59,Ni-62,Ni-63, Ge-70,Ge-72,Ge-73, Zr-90,Zr-91,Zr-92,Zr-93,Zr-94,Zr-96, La-139, Ce-140, Pm-147, Sm-151,Gd- 154,Gd-155,Gd-157, Tm-171, Os-186,Os-187,Os-188, Au-197, Tl-203,Tl-204,Pb- 204,Pb-206,Pb-207 and Bi-209 isotopes, while others are being studied or planned to be studied in the near future. In this contribution, we present an overview of the most successful achievements, and an outlook of future challenging measurements, including ongoing detection system developments.
Address [Massimi, Cristian] Univ Bologna, Dept Phys & Astron, I-40127 Bologna, Italy, Email: cristian.massimi@unibo.it;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000762514400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5144
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Author (up) 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
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 Thesis
Publisher Amer 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 0556-2813 ISBN Medium
Area Expedition Conference
Notes WOS:000303069400003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 994
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Author (up) n_TOF Collaboration (Massimi, C. et al); Domingo-Pardo, C.; Tain, J.L.
Title Au-197(n,gamma) cross section in the resonance region Type Journal Article
Year 2010 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 81 Issue 4 Pages 044616 - 22pp
Keywords
Abstract The (n,gamma) cross section of Au-197 has been measured at nTOF in the resolved resonance region, up to 5 keV, with the aim of improving the accuracy in an energy range where it is not yet considered standard. The measurements were performed with two different experimental setup and detection techniques, the total energy method based on C6D6 detectors, and the total absorption calorimetry based on a 4 pi BaF2 array. By comparing the data collected with the two techniques, two accurate sets of neutron-capture yields have been obtained, which could be the basis for a new evaluation leading to an extended cross-section standard. Overall good agreement is found between the n_TOF results and evaluated cross sections, with some significant exceptions for small resonances. A few resonances not included in the existing databases have also been observed.
Address [Domingo-Pardo, C.] GSI Helmholtzzentrum Schwerionenforsch GmbH, Darmstadt, Germany, Email: c.domingopardo@gsi.de
Corporate Author Thesis
Publisher Amer 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 0556-2813 ISBN Medium
Area Expedition Conference
Notes ISI:000277209500051 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 463
Permanent link to this record