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Yakushev, A.*; Lens, L.*; Dllmann, Ch. E.*; Khuyagbaatar, J.*; Jger, E.*; Krier, J.*; Runke, J.*; Albers, H. M.*; Asai, Masato; Block, M.*; et al.
Frontiers in Chemistry (Internet), 10, p.976635_1 - 976635_11, 2022/08
Times Cited Count:9 Percentile:79.28(Chemistry, Multidisciplinary)Flerovium (Fl, element 114) is the heaviest element chemically studied so far. The first chemical experiment on Fl suggested that Fl is a noble-gas-like element, while the second studies suggested that Fl has a volatile-metal-like character. To obtain more reliable conclusion, we performed further experimental studies on Fl adsorption behavior on Si oxide and gold surfaces. The present results suggest that Fl is highly volatile and less reactive than the volatile metal, Hg, but has higher reactivity than the noble gas, Rn.
Fournier, C.*; Barberet, P.*; Pouthier, T.*; Ritter, S.*; Fischer, B.*; Voss, K.-O.*; Funayama, Tomoo; Hamada, Nobuyuki*; Kobayashi, Yasuhiko; Taucher-Scholz, G.*
Radiation Research, 171(5), p.530 - 540, 2009/05
Times Cited Count:44 Percentile:76.99(Biology)Domingo-Pardo, C.*; Abbondanno, U.*; Aerts, G.*; 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 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 Pb sample. We obtain a Maxwellian average capture cross section for Pb at = 30 keV of 79(3) mb, in agreement with previous experiments. However our cross section at = 5 keV is about 35 % larger than the values reported so far. The implications of the new cross section for the -process abundance contributions in the Pb/Bi region are discussed.
Domingo-Pardo, C.*; Abbondanno, U.*; Aerts, G.*; 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 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 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 778 % to the solar abundance of Pb.
Domingo-Pardo, C.*; Abbondanno, U.*; Aerts, G.*; 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 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 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 = 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.
Aerts, G.*; Abbondanno, U.*; 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 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.
Aerts, G.*; Abbondanno, U.*; 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 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.
Domingo-Pardo, C.*; O'Brien, S.*; Abbondanno, U.*; Aerts, G.*; 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 Pb and 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 Pb we have determined by first time the capture cross sections for two strong -wave resonances below 2.5 keV. In 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.
Terlizzi, R.*; Abbondanno, U.*; Aerts, G.*; 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 La relative to 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 La abundance synthesized in a steller model of the main component of the process.
Mastinu, P. F.*; Abbondanno, U.*; Aerts, G.*; 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.
Schroer, C.*; Voss, Z.*; Wedemeyer, O.*; Novotny, J.*; Konys, J.*; Heinzel, A.*; Weisenburger, A.*; Mller, G.*; Furukawa, Tomohiro; Aoto, Kazumi
JNC TY9400 2005-020, 45 Pages, 2005/08
This report summarises the results of exposure experiments on the behaviour of 12Cr-2W steel P122 and an 9Cr-2W ODS-steel in oxygen-containing flowing lead-bismuth eutectic (LBE) at 550C, which were performed in the CORRIDA loop at the Karlsruhe Lead Laboratory (KALLA) as part of the collaboration between the Japan Nuclear Cycle Development Institute and the Karlsruhe Research Centre. The duration of these experiments was nominally 800, 2000, 5000 and 10,000 h. Both steels were tested after surface-finishing by turning and after surface alloying with aluminium in the GESA-facility. Owing to initial problems with the enrichment of oxygen in the flowing LBE, the oxygen content considerably varied during most of these experiments, so that the influence of temporary changes in the oxygen content of the LBE could also be investigated. The behaviour of P122 and ODS at permanently high oxygen content was deduced from an experiment for 4990 h at 550C and (c 510 mass-% or a 10). The results are compared with the findings of exposures to stagnant LBE at 550C and c=10 mass-% (COSTA-experiments).
Schroer, C.*; Voss, Z.*; Wedemeyer, O.*; Novotny, J.*; Konys, J.*; Heinzel, A.*; Weisenburger, A.*; Mller, G.*; Furukawa, Tomohiro; Aoto, Kazumi
JNC TY9400 2005-019, 26 Pages, 2005/08
This report summarises the results of exposure experiments on the behaviour of 12Cr-2W steel P122 joined by multi-run TIG welding in oxygen-containing flowing lead-bismuth eutectic (LBE) at 550C for nominally 800, 2000 and 5000 h. The flow velocity of the LBE and the mean oxygen content were 2 m/s and 510-7 mass-% (aPbO = 10-3), respectively. The influence of surface-alloying with aluminium (GESA-treatment) was also investigated in an exposure experiment for nominally 5000 h. The behaviour of the welded joint is generally comparable to that of P122 (after the standard heat-treatment), both qualitatively and quantitatively. Only few exceptions were observed which probably result from local peculiarities of the specific sample material. After surface alloying with aluminium, no significant oxidation and no liquid metal corrosion occurred in the centre of the specimens (including the weld seam), where the desired high quality of the aluminised layer was achieved.
Cano-Ott, D.*; Abbondanno, U.*; Aerts, G.*; lvarez, H.*; 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 Np, Pu and 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.
Furman, W.*; Cennini, P.*; Ketlerov, V.*; Goverdovski, A.*; Konovalov, V.*; Abbondanno, U.*; Aerts, G.*; lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; et al.
AIP Conference Proceedings 769, p.1039 - 1042, 2005/05
A series of measurements of 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 Np is required.
Schroer, G.*; Voss, V.*; Wedemeyer, O.*; Novotny, J.*; Konys, J.*; Heinzel, A.*; Weisenburger, A.*; Mller, G.*; Furukawa, Tomohiro; Aoto, Kazumi
JNC TY9400 2004-023, 37 Pages, 2004/05