Refine your search:     
Report No.
 - 
Search Results: Records 1-14 displayed on this page of 14
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

High accuracy, high resolution $$^{235}$$U(n,f) cross section from n_TOF (CERN) from 18 meV to 10 keV

Mastromarco, M.*; Amaducci, S.*; Colonna, N.*; Kimura, Atsushi; 118 of others*

European Physical Journal A, 58(8), p.147_1 - 147_13, 2022/08

 Times Cited Count:2 Percentile:52.69(Physics, Nuclear)

Journal Articles

Comparison of heavy-ion transport simulations; Collision integral in a box

Zhang, Y.-X.*; Wang, Y,-J.*; Colonna, M.*; Danielewicz, P.*; Ono, Akira*; Tsang, M. B.*; Wolter, H.*; Xu, J.*; Chen, L.-W.*; Cozma, D.*; et al.

Physical Review C, 97(3), p.034625_1 - 034625_20, 2018/03

 Times Cited Count:98 Percentile:99.11(Physics, Nuclear)

International comparison of heavy-ion induced reaction models were discussed in the international conference "Transport2017" held in April 2017. Owing to their importance for safety assessment of heavy-ion accelerators and dosimetry of astronauts, various models to simulate heavy-ion induced reaction models are developed. This study is intended to clarify the difference among them to pinpoint their problems. In the comparison study, 320 protons and 320 neutrons were packed in a 20-fm-large cube to calculate the number of particle-particle collisions as well as the energies of collisions during the time evolution. In addition to the calculation, their algorithms were compared. The author contributed to this study by running calculation using JQMD (JAERI Quantum Molecular Dynamics). The results were compared with those calculated by the other 15 codes from over the world. Algorithm comparison showed that JQMD calculates collision probabilities from protons at first and collisions by neutrons are simulated later, which might be unreasonable. On the other hand, it was clarified that the calculation by JQMD agrees with those by the others. Despite the fact that some codes deviate from the average by a factor of 2, JQMD exhibited stable performance.

Journal Articles

Measurement of the $$^{240}$$Pu(n,f) cross-section at the CERN n_TOF facility; First results from experimental area II (EAR-2)

Stamatopoulos, A.*; Tsinganis, A.*; Colonna, N.*; Harada, Hideo; Kimura, Atsushi; n_TOF Collaboration*; 126 of others*

EPJ Web of Conferences, 146, p.04030_1 - 04030_4, 2017/09

 Times Cited Count:6 Percentile:95.25(Nuclear Science & Technology)

Journal Articles

$$^7$$Be(n,$$alpha$$) and $$^7$$Be(n,p) cross-section measurement for the cosmological lithium problem at the n_TOF facility at CERN

Barbagallo, M.*; Colonna, N.*; Aberle, O.*; Harada, Hideo; Kimura, Atsushi; n_TOF Collaboration*; 125 of others*

EPJ Web of Conferences, 146, p.01012_1 - 01012_4, 2017/09

 Times Cited Count:1 Percentile:61.21(Nuclear Science & Technology)

Journal Articles

Measurement of the neutron capture cross section of the $$s$$-only isotope $$^{204}$$Pb from 1 eV to 440 keV

Domingo-Pardo, C.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; et al.

Physical Review C, 75(1), p.015806_1 - 015806_9, 2007/01

 Times Cited Count:34 Percentile:86.95(Physics, Nuclear)

The neutron capture cross section of $$^{204}$$Pb has been measured at the CERN n_TOF installation with high resolution in the energy range from 1 eV to 440 keV. In the interval between 100 keV and 440 keV we report the average cross section. The background in the entire energy range was reliably determined from the measurement of a $$^{208}$$Pb sample. We obtain a Maxwellian average capture cross section for $$^{204}$$Pb at $$kT$$ = 30 keV of 79(3) mb, in agreement with previous experiments. However our cross section at $$kT$$ = 5 keV is about 35 % larger than the values reported so far. The implications of the new cross section for the $$s$$-process abundance contributions in the Pb/Bi region are discussed.

Journal Articles

Resonance capture cross section of $$^{207}$$Pb

Domingo-Pardo, C.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; et al.

Physical Review C, 74(5), p.055802_1 - 055802_6, 2006/11

 Times Cited Count:27 Percentile:81.32(Physics, Nuclear)

The radiative neutron capture cross section of $$^{207}$$Pb has been measured at the CERN n_TOF facility using the pulse height weighting technique in the resoleved region. The measurement has been performed with an optimized setup of two $$C_{6}D_{6}$$ scintillation detectors, which allowed us to reduce scattered neutron backgrounds down to a negligible level. Resonance parameters have been determined for 16 resonances by means of an R-matrix analysis in the neutron energy range from 3 keV to 320 keV. Good agreement with previous measurements was found at low neutron energies, whereas substantial discrepancies appear beyond 45 keV. With the present results, we obtain an s-process contribution of 77$$pm$$8 % to the solar abundance of $$^{207}$$Pb.

Journal Articles

New measurement of neutron capture resonances in $$^{209}$$Bi

Domingo-Pardo, C.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; et al.

Physical Review C, 74(2), p.025807_1 - 025807_10, 2006/08

 Times Cited Count:47 Percentile:90.41(Physics, Nuclear)

The neutron capture cross section of $$^{209}$$Bi has been measured at the CERN n_TOF facility by employing the pulse-height-weighting technique. Improvements over previous measurements are mainly because of an optimized detection system, which led to a practically negligible neutron sensitivity. Because $$^{209}$$Bi is the last stable isotope in the reaction path of the stellar s-process, the Maxwellian averaged capture cross section is important for the recycling of the reaction flow by alpha decays. In the relevant stellar range of thermal energies between $$kT$$ = 5 and 8 keV our new capture rate is about 16% higher than the presently accepted value used for nucleosynthesis calculations. The present cross section measurement is also of relevance for the design of accelerator driven systems based on a liquid metal Pb/Bi spallation target.

Journal Articles

Neutron capture cross section of $$^{232}$$Th measured at the n_TOF facility at CERN in the unresolved resonance region up to 1 MeV

Aerts, G.*; Abbondanno, U.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; Baumann, P.*; et al.

Physical Review C, 73(5), p.054610_1 - 054610_10, 2006/05

We have measured the neutron capture reaction yield of $$^{232}$$Th at the neutron tim-of-flight facility n_TOF at CERN in the energy range from 1 eV to 1 MeV. The average capture cross section has been extracted in the energy range from 4 keV up to 1 MeV with an overall accuracy better than 4 %. An independent IAEA evaluation shows good agreement with the data.

Journal Articles

Neutron capture cross section of $$^{232}$$Th measured at the n_TOF facility at CERN in the unresolved resonance region up to 1 MeV

Aerts, G.*; Abbondanno, U.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; Baumann, P.*; et al.

Physical Review C, 73(5), p.054610_1 - 054610_10, 2006/05

 Times Cited Count:45 Percentile:89.88(Physics, Nuclear)

We have measured the neutron capture reaction yield of $$^{232}$$Th at the neutron time-of-flight facility n_TOF at CERN in the energy range from 1 eV to 1 MeV. The average capture cross section has been extracted in the energy range from 4 keV up to 1 MeV with an overall accuracy better than 4%. An independent IAEA evaluation shows good agreement with the data.

Journal Articles

Measurement of the resonance capture cross section of $$^{204,206}$$Pb and termination of the $$s$$-process

Domingo-Pardo, C.*; O'Brien, S.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; et al.

AIP Conference Proceedings 819, p.288 - 292, 2006/03

The neutron capture cross sections of $$^{204}$$Pb and $$^{206}$$Pb have been measured at the CERN n_TOF installation using the time of flight method with the pulse height weighting technique. In a preliminary analysis of $$^{204}$$Pb we have determined by first time the capture cross sections for two strong $$s$$-wave resonances below 2.5 keV. In $$^{206}$$Pb we have determined capture cross sections for a large number of resonances, which were not reported in the two previous capture measurements. We discuss preliminary implications of the new cross sections in the stellar nucleosynthesis of the Pb isotopes.

Journal Articles

Measurement of $$^{139}$$La($$n$$,$$gamma$$) cross section

Terlizzi, R.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; et al.

AIP Conference Proceedings 819, p.283 - 287, 2006/03

We measured the neutron capture cross section of $$^{139}$$La relative to $$^{197}$$Au in the energy range of 0.6 eV to 9 keV at n_TOF, the neutron time-of-flight facility at CERN. The data were fitted using R-matrix formalism to extract resonance parameters which were used to calculate average level spacings. The data were used to determine Maxwellian-averaged neutron capture cross sections which, in turn, were used to calculate the $$^{139}$$La abundance synthesized in a steller model of the main component of the $$s$$ process.

Journal Articles

Neutron cross section measurements at n-TOF for ADS related studies

Mastinu, P. F.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; et al.

Journal of Physics; Conference Series, 41, p.352 - 360, 2006/00

A neutron Time-of-Flight facility (n_TOF) is operative at CERN since 2001. The innovative features of the neutron beam, in particular the high instantaneous flux, the wide energy range, the high resolution and the low background, makes this facility unique for measurements of neutron induced reactions relevant to the field of Emerging Nuclear Technologies, as well as to Nuclear Astrophysics and fundamental Nuclear Physics. The scientific motivations that have led to the construction of this new facility are here presented.

Journal Articles

Measurements at n_TOF of the neutron capture cross section of minor actinides relevant to the nuclear waste transmutation

Cano-Ott, D.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; $'A$lvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; et al.

AIP Conference Proceedings 769, p.1442 - 1445, 2005/05

Accurate and reliable neutron cross section data for actinides are necessary for the proper design, safety reguartion and precise performance assessment of transmutaion devices. In particular, the neutron capture cross sections of $$^{237}$$Np, $$^{240}$$Pu and $$^{243}$$Am play a key role in the design and optimization of a strategy for the Nuclear Waste Transmutation. The listed cross sections have been measured in 2004 at n_TOF with a high accuracy due to a combination of features unique in the world.

Journal Articles

High-resolution study of $$^{237}$$Np fission cross section from 5 eV to 1 MeV

Furman, W.*; Cennini, P.*; Ketlerov, V.*; Goverdovski, A.*; Konovalov, V.*; Abbondanno, U.*; Aerts, G.*; $'A$lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; et al.

AIP Conference Proceedings 769, p.1039 - 1042, 2005/05

A series of measurements of $$^{237}$$Np fission cross section have been performed at the CERN spallation neutron source facility n_TOF. A fast ionization chamber was used as a fission fragment detector. Total experimental uncertainties are determined to be at the level of 3%. Analysis of experimental data in the neutron energy from 5 eV to 1 MeV showed a systematic deviation from the evaluated data (ENDF/B-VI). This discrepancy amounts to up to the factor of 3 for resolved resonances in the neutron energy range of 5 eV - 2 keV, and is in good agreement with some previous experiments. A similar disagreement at the level of 6-7% was found for higher energies around the threshold. This energy range is essential for the transmutation of neptunium in ADS or fast reactors. It is concluded that an updated evaluation of nuclear data for $$^{237}$$Np is required.

14 (Records 1-14 displayed on this page)
  • 1