Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 111

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

The Joint evaluated fission and fusion nuclear data library, JEFF-3.3

Plompen, A. J. M.*; Cabellos, O.*; De Saint Jean, C.*; Fleming, M.*; Algora, A.*; Angelone, M.*; Archier, P.*; Bauge, E.*; Bersillon, O.*; Blokhin, A.*; et al.

European Physical Journal A, 56(7), p.181_1 - 181_108, 2020/07

 Times Cited Count:5 Percentile:8.7(Physics, Nuclear)

The Joint Evaluated Fission and Fusion nuclear data library 3.3 is described. New evaluations for neutron-induced interactions with the major actinides $$^{235}$$U, $$^{238}$$U and $$^{239}$$Pu, on $$^{241}$$Am and $$^{23}$$Na, $$^{59}$$Ni, Cr, Cu, Zr, Cd, Hf, W, Au, Pb and Bi are presented. It includes new fission yileds, prompt fission neutron spectra and average number of neutrons per fission. In addition, new data for radioactive decay, thermal neutron scattering, gamma-ray emission, neutron activation, delayed neutrons and displacement damage are presented. JEFF-3.3 was complemented by files from the TENDL project. The libraries for photon, proton, deuteron, triton, helion and alpha-particle induced reactions are from TENDL-2017. The demands for uncertainty quantification in modeling led to many new covariance data. A comparison between results from model calculations using the JEFF-3.3 library and those from benchmark experiments for criticality, delayed neutron yields, shielding and decay heat, reveals that JEFF-3.3 is excellent for a wide range of nuclear technology applications, in particular nuclear energy.

Journal Articles

Shell structure of the neutron-rich isotopes $$^{69,71,73}$$Co

Lokotko, T.*; Leblond, S.*; Lee, J.*; Doornenbal, P.*; Obertelli, A.*; Poves, A.*; Nowacki, F.*; Ogata, Kazuyuki*; Yoshida, Kazuki; Authelet, G.*; et al.

Physical Review C, 101(3), p.034314_1 - 034314_7, 2020/03

 Times Cited Count:1 Percentile:100(Physics, Nuclear)

The structures of the neutron-rich $$^{69,71,73}$$Co isotopes were investigated via ($$p,2p$$) knockout reactions at the Radioactive Isotope Beam Factory, RIKEN. Level schemes were reconstructed using the $$gamma-gamma$$ coincidence technique, with tentative spin-parity assignments based on the measured inclusive and exclusive cross sections. Comparison with shell-model calculations suggests coexistence of spherical and deformed shapes at low excitation energies in the $$^{69,71,73}$$Co isotopes.

Journal Articles

Pressure-induced Diels-Alder reactions in C$$_{6}$$H$$_{6}$$ - C$$_{6}$$F$$_{6}$$ cocrystal towards graphane structure

Wang, Y.*; Dong, X.*; Tang, X.*; Zheng, H.*; Li, K.*; Lin, X.*; Fang, L.*; Sun, G.*; Chen, X.*; Xie, L.*; et al.

Angewandte Chemie; International Edition, 58(5), p.1468 - 1473, 2019/01

 Times Cited Count:4 Percentile:48.41(Chemistry, Multidisciplinary)

Pressure-induced polymerization (PIP) of aromatics is a novel method to construct sp$$^{3}$$-carbon frameworks, and nanothreads with diamond-like structures were synthesized by compressing benzene and its derivatives. Here by compressing benzene-hexafluorobenzene cocrystal(CHCF), we identified H-F-substituted graphane with a layered structure in the PIP product. Based on the crystal structure determined from the in situ neutron diffraction and the intermediate products identified by the gas chromatography-mass spectrum, we found that at 20 GPa CHCF forms tilted columns with benzene and hexafluorobenzene stacked alternatively, which leads to a [4+2] polymer, and then transfers to short-range ordered hydrogenated-fluorinated graphane. The reaction process contains [4+2] Diels-Alder, retro-Diels-Alder, and 1-1' coupling, and the former is the key reaction in the PIP. Our studies confirmed the elemental reactions of the CHCF for the first time, which provides a novel insight into the PIP of aromatics.

Journal Articles

Nuclear structure of $$^{76}$$Ni from the ($$p$$,$$2p$$) reaction

Elekes, Z.*; Kripk$'o$, $'A$*; Sohler, D.*; Sieja, K.*; Ogata, Kazuyuki*; Yoshida, Kazuki; Doornenbal, P.*; Obertelli, A.*; Authelet, G.*; Baba, Hidetada*; et al.

Physical Review C, 99(1), p.014312_1 - 014312_7, 2019/01

 Times Cited Count:3 Percentile:27.46(Physics, Nuclear)

The nuclear structure of the $$^{76}$$Ni nucleus was investigated by ($$p$$,$$2p$$) reaction using a NaI(Tl) array to detect the deexciting prompt $$gamma$$ rays. A new transition with an energy of 2227 keV was identified by $$gamma gamma$$ and $$gamma gamma gamma$$ coincidences. Our shell-model calculations using the Lenzi, Nowacki, Poves, and Sieja interaction produced good candidates for the experimental proton hole states in the observed energy region, and the theoretical cross sections showed good agreement with the experimental values. Although we could not assign all the experimental states to the theoretical ones unambiguously, the results are consistent with a reasonably large Z = 28 shell gap for nickel isotopes in accordance with previous studies.

Journal Articles

Investigation of the electronic structure and lattice dynamics of the thermoelectric material Na-doped SnSe

Wu, P.*; Zhang, B.*; Peng, K. L.*; Hagiwara, Masayuki*; Ishikawa, Yoshihisa*; Kofu, Maiko; Lee, S. H.*; Kumigashira, Hiroshi*; Hu, C. S.*; Qi, Z. M.*; et al.

Physical Review B, 98(9), p.094305_1 - 094305_7, 2018/09

 Times Cited Count:4 Percentile:55.32(Materials Science, Multidisciplinary)

Using angle-resolved photoemission spectroscopy and inelastic neutron scattering, we have studied how electronic structures and lattice dynamics evolve with temperature in Na-doped SnSe.

Journal Articles

Overall approaches and experiences of first-time participants in the Nuclear Forensics International Technical Working Group's Fourth Collaborative Material Exercise (CMX-4)

Ho, D. M. L.*; Nelwamondo, A. N.*; Okubo, Ayako; Rameb$"a$ck, H.*; Song, K.*; Han, S.-H.*; Hancke, J. J.*; Holmgren, S.*; Jonsson. S.*; Kataoka, Osamu; et al.

Journal of Radioanalytical and Nuclear Chemistry, 315(2), p.353 - 363, 2018/02

 Times Cited Count:0 Percentile:100(Chemistry, Analytical)

The Fourth Collaborative Material Exercise (CMX-4) of the Nuclear Forensics International Technical Working Group (ITWG) registered the largest participation for this exercise in nuclear forensics, with seven of the 17 laboratories participating for the first time. In this paper, participants from five of the first-time laboratories shared their individual experience in this exercise, from preparation to analysis of samples. The exercise proved to be highly useful for testing procedures, repurposing established methods, exercising skills, and improving the understanding of nuclear forensic signatures and their interpretation trough the post-exercise review meeting.

Journal Articles

The Application of radiochronometry during the 4th collaborative materials exercise of the nuclear forensics international technical working group (ITWG)

Kristo, M. J.*; Williams, R.*; Gaffney, A. M.*; Kayzar-Boggs, T. M.*; Schorzman, K. C.*; Lagerkvist, P.*; Vesterlund, A.*; Rameb$"a$ck, H.*; Nelwamondo, A. N.*; Kotze, D.*; et al.

Journal of Radioanalytical and Nuclear Chemistry, 315(2), p.425 - 434, 2018/02

 Times Cited Count:4 Percentile:29.78(Chemistry, Analytical)

In a recent international exercise, 10 international nuclear forensics laboratories successfully performed radiochronometry on three low enriched uranium oxide samples, providing 12 analytical results using three different parent-daughter pairs serving as independent chronometers. The vast majority of the results were consistent with one another and consistent with the known processing history of the materials. In general, for these particular samples, mass spectrometry gave more accurate and more precise analytical results than decay counting measurements. In addition, the concordance of the $$^{235}$$U-$$^{231}$$Pa and $$^{234}$$U-$$^{230}$$Th chronometers confirmed the validity of the age dating assumptions, increasing confidence in the resulting conclusions.

Journal Articles

CIELO collaboration summary results; International evaluations of neutron reactions on uranium, plutonium, iron, oxygen and hydrogen

Chadwick, M. B.*; Capote, R.*; Trkov, A.*; Herman, M. W.*; Brown, D. A.*; Hale, G. M.*; Kahler, A. C.*; Talou, P.*; Plompen, A. J.*; Schillebeeckx, P.*; et al.

Nuclear Data Sheets, 148, p.189 - 213, 2018/02

 Times Cited Count:22 Percentile:3.55(Physics, Nuclear)

The CIELO collaboration has studied neutron cross sections on nuclides that significantly impact criticality in nuclear facilities - $$^{235}$$U, $$^{238}$$U, $$^{239}$$Pu, $$^{56}$$Fe, $$^{16}$$O and $$^{1}$$H - with the aim of improving the accuracy of the data and resolving previous discrepancies in our understanding. This multi-laboratory pilot project, coordinated via the OECD/NEA Working Party on Evaluation Cooperation (WPEC) Subgroup 40 with support also from the IAEA, has motivated experimental and theoretical work and led to suites of new evaluated libraries that accurately reflect measured data and also perform well in integral simulations of criticality. This report summarizes our results and outlines plans for the next phase of this collaboration.

Journal Articles

Shell evolution beyond $$Z$$=28 and $$N$$=50; Spectroscopy of $$^{81,82,83,84}$$Zn

Shand, C. M.*; Podoly$'a$k, Zs.*; G$'o$rska, M.*; Doornenbal, P.*; Obertelli, A.*; Nowacki, F.*; Otsuka, T.*; Sieja, K.*; Tostevin, J. A.*; Tsunoda, T.*; et al.

Physics Letters B, 773, p.492 - 497, 2017/10

 Times Cited Count:13 Percentile:13.18(Astronomy & Astrophysics)

Journal Articles

The CIELO collaboration; Progress in international evaluations of neutron reactions on Oxygen, Iron, Uranium and Plutonium

Chadwick, M. B.*; Capote, R.*; Trkov, A.*; Kahler, A. C.*; Herman, M. W.*; Brown, D. A.*; Hale, G. M.*; Pigni, M.*; Dunn, M.*; Leal, L.*; et al.

EPJ Web of Conferences, 146, p.02001_1 - 02001_9, 2017/09

 Times Cited Count:5 Percentile:1.55

The CIELO collaboration has studied neutron cross sections on nuclides ($$^{16}$$O, $$^{56}$$Fe, $$^{235,238}$$U and $$^{239}$$Pu) that significantly impact criticality in nuclear technologies with the aim of improving the accuracy of the data and resolving previous discrepancies in our understanding. This multi-laboratory pilot project, coordinated via the OECD/NEA Working Party on Evaluation Cooperation (WPEC) Subgroup 40 with support also from the IAEA, has motivated experimental and theoretical work and led to suites of new evaluated libraries that accurately reflect measured data and also perform well in integral simulations of criticality.

Journal Articles

Shape evolution in neutron-rich krypton isotopes beyond N=60; First spectroscopy of $$^{98,100}$$Kr

Flavigny, F.*; Doornenbal, P.*; Obertelli, A.*; Delaroche, J.-P.*; Girod, M.*; Libert, J.*; Rodriguez, T. R.*; Authelet, G.*; Baba, Hidetada*; Calvet, D.*; et al.

Physical Review Letters, 118(24), p.242501_1 - 242501_6, 2017/06

 Times Cited Count:21 Percentile:11.07(Physics, Multidisciplinary)

Journal Articles

Low-lying structure and shape evolution in neutron-rich Se isotopes

Chen, S.*; Doornenbal, P.*; Obertelli, A.*; Rodriguez, T. R.*; Authelet, G.*; Baba, Hidetada*; Calvet, D.*; Ch$^a$teau, F.*; Corsi, A.*; Delbart, A.*; et al.

Physical Review C, 95(4), p.041302_1 - 041302_6, 2017/04

 Times Cited Count:15 Percentile:10.36(Physics, Nuclear)

Journal Articles

Are there signatures of harmonic oscillator shells far from stability?; First spectroscopy of $$^{110}$$Zr

Paul, N.*; Corsi, A.*; Obertelli, A.*; Doornenbal, P.*; Authelet, G.*; Baba, Hidetada*; Bally, B.*; Bender, M.*; Calvet, D.*; Ch$^a$teau, F.*; et al.

Physical Review Letters, 118(3), p.032501_1 - 032501_7, 2017/01

 Times Cited Count:23 Percentile:9.8(Physics, Multidisciplinary)

Journal Articles

Ultra-trace analysis of plutonium by thermal ionization mass spectrometry with a continuous heating technique without chemical separation

Lee, C.-G.*; Suzuki, Daisuke; Esaka, Fumitaka; Magara, Masaaki; Song, K.*

Talanta, 141, p.92 - 96, 2015/08

 Times Cited Count:9 Percentile:54.63(Chemistry, Analytical)

Thermal ionization mass spectrometry (TIMS) with a continuous heating technique is known as an effective method for measuring the isotope ratio in trace amounts of uranium. In this study, the analytical performance of thermal ionization mass spectrometry with a continuous heating technique was investigated using a standard plutonium solution (SRM 947). The influence of the heating rate of the evaporation filament on the precision and accuracy of the isotope ratios was examined using a plutonium solution sample at the fg level. Changing the heating rate of the evaporation filament on samples ranging from 0.1 fg to 1000 fg revealed that the influence of the heating rate on the precision and accuracy of the isotope ratios was slight around the heating rate range of 100 to 250 mA/min. All of the isotope ratios of plutonium (SRM 947), $$^{238}$$Pu/$$^{239}$$Pu, $$^{240}$$Pu/$$^{239}$$Pu, $$^{241}$$Pu/$$^{239}$$Pu and $$^{242}$$Pu/$$^{239}$$Pu, were measured down to sample amounts of 70 fg. The ratio of $$^{240}$$Pu/$$^{239}$$Pu was measured down to a sample amount of 0.1 fg, which corresponds to a PuO$$_{2}$$ particle with a diameter of 0.2 $$mu$$m. Moreover, the signals of $$^{239}$$Pu could be detected with a sample amount of 0.03 fg, which corresponds to the detection limit of $$^{239}$$Pu of 0.006 fg as estimated by the 3 $$sigma$$ criterion. $$^{241}$$Pu and $$^{241}$$Am formed by the decay of $$^{241}$$Pu could be discriminated owing to the difference in the evaporation temperature. As a result, $$^{241}$$Pu/$$^{239}$$Pu as well as $$^{240}$$Pu/$$^{239}$$Pu and $$^{242}$$Pu/$$^{239}$$Pu in plutonium samples could be measured by TIMS with a continuous heating technique and without any chemical separation processes.

Journal Articles

Neutron spectroscopic factors of $$^{55}$$Ni hole-states from (p,d) transfer reactions

Sanetullaev, A.*; Tsang, M. B.*; Lynch, W. G.*; Lee, J.*; Bazin, D.*; Chan, K. P.*; Coupland, D.*; Hanzl, V.*; Hanzlova, D.*; Kilburn, M.*; et al.

Physics Letters B, 736, p.137 - 141, 2014/09

 Times Cited Count:10 Percentile:34.35(Astronomy & Astrophysics)

no abstracts in English

Journal Articles

The CIELO Collaboration; Neutron reactions on $$^1$$H, $$^{16}$$O, $$^{56}$$Fe, $$^{235,238}$$U, and $$^{239}$$Pu

Chadwick, M. B.*; Dupont, E.*; Bauge, E.*; Blokhin, A.*; Bouland, O.*; Brown, D. A.*; Capote, R.*; Carlson, A. D.*; Danon, Y.*; De Saint Jean, C.*; et al.

Nuclear Data Sheets, 118, p.1 - 25, 2014/04

 Times Cited Count:90 Percentile:1.18(Physics, Nuclear)

CIELO (Collaborative International Evaluated Library Organization) provides a new working paradigm to facilitate evaluated nuclear reaction data advances. It brings together experts from across the international nuclear reaction data community to identify and document discrepancies among existing evaluated data libraries, measured data, and model calculation interpretations, and aims to make progress in reconciling these discrepancies to create more accurate ENDF-formatted files. The focus will initially be on a small number of the highest-priority isotopes, namely $$^{1}$$H, $$^{16}$$O, $$^{56}$$Fe, $$^{235,238}$$U, and $$^{239}$$Pu. This paper identifies discrepancies between various evaluations of the highest priority isotopes. The evaluated data for these materials in the existing nuclear data libraries are reviewed, and some integral properties are given. The paper summarizes a program of nuclear science and computational work needed to create the new CIELO nuclear data evaluations.

Journal Articles

Spatio-temporal evolution of the L$$rightarrow$$H and H$$rightarrow$$L transitions

Miki, Kazuhiro; Diamond, P. H.*; Fedorczak, N.*; G$"u$rcan, $"O$. D.*; Malkov, M.*; Lee, C.*; Kosuga, Yusuke*; Tynan, G. R.*; Xu, G. S.*; Estrada, T.*; et al.

Nuclear Fusion, 53(7), p.073044_1 - 073044_10, 2013/07

 Times Cited Count:19 Percentile:25.16(Physics, Fluids & Plasmas)

Understanding the L$$rightarrow$$H and H$$rightarrow$$L transitions is crucial to successful ITER operation. In this paper we present novel theoretical and modelling study results on the spatio-temporal dynamics of the transition. We place a special emphasis on the role of zonal flows and the micro$$rightarrow$$macro connection between dynamics and the power threshold dependences. The model studied evolves five coupled fields in time and one space dimension, in simplified geometry. The content of this paper is (a) the model fundamentals and the space-time evolution during the L$$rightarrow$$I$$rightarrow$$H transition, (b) the physics origin of the well-known $$nabla$$ B-drift asymmetry in power threshold, (c) the role of heat avalanches in the intrinsic variability of the L$$rightarrow$$H transition, (d) the dynamics of the H$$rightarrow$$L back transition and the physics of hysteresis.

Journal Articles

Fission track-secondary ion mass spectrometry as a tool for detecting the isotopic signature of individual uranium containing particles

Esaka, Fumitaka; Lee, C. G.; Magara, Masaaki; Kimura, Takaumi

Analytica Chimica Acta, 721, p.122 - 128, 2012/04

 Times Cited Count:26 Percentile:25.38(Chemistry, Analytical)

A fission track technique was used as a sample preparation method for subsequent isotope abundance ratio analysis of individual uranium containing particles with secondary ion mass spectrometry (SIMS) to measure the particles with higher enriched uranium efficiently. This method was then applied to the analysis of a real inspection swipe sample taken at a nuclear facility. As a consequence, the range of $$^{235}$$U/$$^{238}$$U isotope abundance ratio between 0.0276 and 0.0438 was obtained, which was higher than that measured by SIMS without using a fission track technique (0.0225 and 0.0341). This indicates that the fission track - SIMS method is a powerful tool to identify the particle with higher enriched uranium in environmental samples efficiently.

Journal Articles

Simultaneous determination of plutonium and uranium isotope ratios in individual plutonium-uranium mixed particles by thermal ionization mass spectrometry

Lee, C. G.; Suzuki, Daisuke; Kokubu, Yoko; Esaka, Fumitaka; Magara, Masaaki; Kimura, Takaumi

International Journal of Mass Spectrometry, 314, p.57 - 62, 2012/03

 Times Cited Count:16 Percentile:26.96(Physics, Atomic, Molecular & Chemical)

In this study, we developed a method for the simultaneous measurement of all the plutonium and uranium isotopes without the need for chemical separation, using thermal ionization mass spectrometry (TIMS) with a continuous heating method. The MOX particles with sizes of 0.6-2.3 $$mu$$m used in this study were made from a mixed solution of plutonium (SRM947) and uranium (U500). The isotope ratios of plutonium and uranium obtained for all the MOX particles, including the ones in the sub-micrometer size range, were in good agreement with the certified values within the range of error. In particular, the determination of the $$^{238}$$Pu/$$^{239}$$Pu isotope ratio, which is difficult because of the isobaric interference of $$^{238}$$U, was performed accurately. The $$^{238}$$Pu/$$^{239}$$Pu ratios were obtained by using a correction in which the background of $$^{238}$$U intensity at the $$^{238}$$Pu peak was estimated from the peak fitting of the $$^{238}$$U signal profile.

Journal Articles

Isotope ratio analysis of individual plutonium and uranium-plutonium mixed oxide particles by thermal ionization mass spectrometry with a continuous heating method

Suzuki, Daisuke; Kokubu, Yoko; Lee, C. G.; Esaka, Fumitaka; Magara, Masaaki; Kimura, Takaumi

Chemistry Letters, 41(1), p.90 - 91, 2012/01

 Times Cited Count:6 Percentile:69.88(Chemistry, Multidisciplinary)

In conventional isotope ratio analysis of individual plutonium particles, the analytical procedure is complicated, because the particles have to be dissolved prior to the measurement. The chemical treatments may cause contamination of $$^{238}$$U existing in the environment. This makes it difficult to obtain accurate $$^{238}$$Pu/$$^{239}$$Pu isotope ratio. In the present work, an analytical method by a combination of single particle transfer and thermal ionization mass spectrometry with a continuous heating method is examined for individual plutonium particles, namely the particles are measured without any chemical treatments. In addition, the technique is applied to the analysis of individual uranium-plutonium mixed oxide (MOX) particles. The results of analysis of individual particles produced from standard solutions indicate that all isotope ratios are consistent with the certified values. There is no effect of isobaric interference on the results. In conclusion, the proposed analytical method is a useful tool for the isotope ratio analysis of plutonium and MOX particles without any chemical treatments.

111 (Records 1-20 displayed on this page)