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Baccou, J.*; Glantz, T.*; Ghione, A.*; Sargentini, L.*; Fillion, P.*; Damblin, G.*; Sueur, R.*; Iooss, B.*; Fang, J.*; Liu, J.*; et al.
Nuclear Engineering and Design, 421, p.113035_1 - 113035_16, 2024/05
In the Best-Estimate Plus Uncertainty (BEPU) framework, the use of best-estimate code requires to go through a Verification, Validation and Uncertainty Quantification process (VVUQ). The relevance of the experimental data in relation to the physical phenomena of interest in the VVUQ process is crucial. Adequacy analysis of selected experimental databases addresses this problem. The outcomes of the analysis can be used to select a subset of relevant experimental data, to encourage designing new experiments or to drop some experiments from a database because of their substantial lack of adequacy. The development of a specific transparent and reproducible approach to analyze the relevance of experimental data for VVUQ still remains open and is the topic of this contribution. In this paper, the concept of adequacy initially introduced in the OECD/NEA SAPIUM (Systematic APproach for model Input Uncertainty quantification Methodology) activity is formalized. It is defined through two key properties, called representativeness and completeness, that allows considering the multifactorial dimension of the adequacy problem. A new systematic approach is then proposed to analyze the adequacy of a set of experimental databases. It relies on the introduction of two sets of criteria to characterize representativeness and completeness and on the use of multi-criteria decision analysis method to perform the analysis. Finally, the approach is applied in the framework of the new OECD/NEA ATRIUM activity which includes a set of practical IUQ exercises in thermal-hydraulics to test the SAPIUM guideline in determining input uncertainties and forward propagating them on an application case. It allows evaluating the adequacy of eight experimental databases coming from the Super Moby-dick, Sozzi-Sutherland and Marviken experiments and identifying the most adequate ones.
Fe(n,
)
Fe cross section from the surrogate ratio method and its effect on the Fe nucleosynthesisYan, S. Q.*; Li, X. Y.*; 西尾 勝久; Lugaro, M.*; Li, Z. H.*; 牧井 宏之; Pignatari, M.*; Wang, Y. B.*; Orlandi, R.; 廣瀬 健太郎; et al.
Astrophysical Journal, 919(2), p.84_1 - 84_7, 2021/10
被引用回数：1 パーセンタイル：8.87(Astronomy & Astrophysics)The long-lived Fe (with a half-life of 2.62 Myr) is a crucial diagnostic of active nucleosynthesis in the Milky Way galaxy and in supernovae near the solar system. The neutron-capture reaction Fe(n,)Fe on Fe (half-life=44.5 days) is the key reaction for the production of Fe in massive stars. This reaction cross section has been previously constrained by the Coulomb dissociation experiment, which offered partial constraint on the E1 -ray strength function but a negligible constraint on the M1 and E2 components. In this work, for the first time, we use the surrogate ratio method to experimentally determine the Fe(n,)Fe cross sections in which all the components are included. We derived a Maxwellian-averaged cross section of 27.5
3.5 mb at 
= 30 keV and 13.41.7 mb at = 90 keV, roughly 10%-20% higher than previous estimates. We analyzed the impact of our new reaction rates in nucleosynthesis models of massive stars and found that uncertainties in the production of Fe from the Fe(n,)Fe rate are at most 25
. We conclude that stellar physics uncertainties now play a major role in the accurate evaluation of the stellar production of Fe.
Zr(
)
Zr cross section from the surrogate ratio method and its effect on 
-process nucleosynthesisYan, S. Q.*; Li, Z. H.*; Wang, Y. B.*; 西尾 勝久; Lugaro, M.*; Karakas, A. I.*; 牧井 宏之; Mohr, P.*; Su, J.*; Li, Y. J.*; et al.
Astrophysical Journal, 848(2), p.98_1 - 98_8, 2017/10
被引用回数：5 パーセンタイル：21.48(Astronomy & Astrophysics)The Zr()Zr reaction cross section is crucial in the modelling of -process nucleosynthesis in asymptotic giant branch stars because it controls the operation of the branching point at the unstable Zr and the subsequent production of Zr. We have carried out the measurement of the 
Zr(
O,
O) and 
Zr(O,O) reactions and obtained the -decay probability ratio of 
Zr
and Zr to determine the Zr()Zr reaction cross sections with the surrogate ratio method. We tested our deduced maxwellian-averaged cross section in stellar models with masses between 2 and 6 
and metallicities 0.014 and 0.03. The largest changes - up 80 % variations in Zr - are seen in the models of 3-4 , where the 
Ne neutron source is mildly activated. The new rate can still provide a match to data from meteoritic stardust silicon carbide grains, provided the maximum mass of the parent stars is below 4 , for a metallicity of 0.03.
=1 Haldane chainTzeng, Y.-C.*; 大西 弘明; 大久保 毅*; Kao, Y.-J.*
Physical Review B, 96(6), p.060404_1 - 060404_7, 2017/08
被引用回数：24 パーセンタイル：72.72(Materials Science, Multidisciplinary)The spin-1 Haldane chain is an example of the symmetry-protected-topological (SPT) phase in one dimension. Experimental realization of the spin chain materials usually involves both the uniaxial-type, 
, and the rhombic-type, ![$$E[(S^x)^2-(S^y)^2]$$](/search/images/ERCVWKCTLZ2CSXRSFUUFGXTZFFPDEXJE.gif)
, single-ion anisotropies. Here, we provide a precise ground-state phase diagram for a spin-1 Haldane chain with these single-ion anisotropies. Using quantum numbers, we find that the 
symmetry breaking phase can be characterized by double degeneracy in the entanglement spectrum. Topological quantum phase transitions take place on particular paths in the phase diagram, from the Haldane phase to the large-
, large-
, or large-
phases. The topological critical points are determined by the level spectroscopy method with a newly developed parity technique in the density matrix renormalization group, and the Haldane-large- critical point is obtained with an unprecedented precision, 
=0.9684713(1). Close to this critical point, a small rhombic single-ion anisotropy 
can destroy the Haldane phase and bring the system into a 
-N
el phase. We propose that the compound [Ni(HF
)(3-Clpy)
]BF is a candidate system to search for the -Nel phase.
Zr(n,)Zr cross section with 
Zr(O,O)
Zr reactionsYan, S. Q.*; Li, Z. H.*; Wang, Y. B.*; 西尾 勝久; 牧井 宏之; Su, J.*; Li, Y. J.*; 西中 一朗; 廣瀬 健太郎; Han, Y. L.*; et al.
Physical Review C, 94(1), p.015804_1 - 015804_5, 2016/07
被引用回数：6 パーセンタイル：44.49(Physics, Nuclear)The relative -decay probability ratios of the neutron resonance states in Zr and Zr populated via two neutron transfer reactions, Zr(O,O)Zr and Zr(O,O)Zr, have been measured to test the validity of the surrogate ratio method (SRM) in determining the (n,) reaction cross section. The cross sections of the Zr(n,)Zr reaction are derived from the experimentally obtained ratios and the cross sections of the 
Zr(n,)Zr reaction in the equivalent neutron energy range of 
= 0 - 8 MeV. The deduced cross sections of Zr(n,)Zr reaction agree with the directly measured ones in the low-energy region, and with the evaluated ENDF/B-VII.1 data at higher energies of 
3 MeV. The agreement supports the concept of the SRM method to indirectly determine the (n,) reaction cross sections.
plasmas on JT-60U and DIII-D松永 剛; 岡林 典男*; 相羽 信行; Boedo, J. A.*; Ferron, J. R.*; Hanson, J. M.*; Hao, G. Z.*; Heidbrink, W. W.*; Holcomb, C. T.*; In, Y.*; et al.
Nuclear Fusion, 53(12), p.123022_1 - 123022_13, 2013/12
被引用回数：6 パーセンタイル：26.2(Physics, Fluids & Plasmas)In the wall-stabilized high- plasmas in JT-60U and DIII-D, interactions between energetic particle (EP) driven modes (EPdMs) and edge localized modes (ELMs) have been observed. The interaction between the EPdM and ELM are reproducibly observed. Many EP diagnostics indicate that strong correlation between the distorted waveform of the EPdM and the EP transport to edge. The waveform distortion is composed of higher harmonics 
and it looks like a density snake near the plasma edge. According to statistical analyses, the ELM triggering by the EPdMs needs finite level of waveform distortion and pedestal recovery. The ELM pacing by the EPdMs occurs when the repetition frequency of the EPdMs is higher than the natural ELM frequency. Transported EPs by the EPdMs are thought to contribute to change the edge stability.
松永 剛; 岡林 典男*; 相羽 信行; Boedo, J. A.*; Ferron, J. R.*; Hanson, J. M.*; Hao, G. Z.*; Heidbrink, W. W.*; Holcomb, C. T.*; In, Y.*; et al.
Proceedings of 24th IAEA Fusion Energy Conference (FEC 2012) (CD-ROM), 8 Pages, 2013/03
In the wall-stabilized high- plasmas in JT-60U and DIII-D, interactions between energetic particle (EP) driven modes and MHD modes such as edge localized modes (ELMs) have been observed. The ELM triggering by EP driven modes (EPdMs) occurs when the repetition frequency of the EPdMs is higher than that of the ELM. The EPdMs have strong waveform distortion that is composed of higher toroidal harmonics. In particular, EP behavior seems to be sensitive to the waveform distortion, thus, waveform distortion can rapidly increase EP transport to edge. According to statistical analysis, the ELM triggering by the EPdMs infrequently occurs just after the ELM crash. Transported EPs by the EPdMs are thought to contribute to change the edge stability.
Schaffer, M. J.*; Snipes, J. A.*; Gohil, P.*; de Vries, P.*; Evans, T. E.*; Fenstermacher, M. E.*; Gao, X.*; Garofalo, A. M.*; Gates, D. A.*; Greenfield, C. M.*; et al.
Nuclear Fusion, 51(10), p.103028_1 - 103028_11, 2011/10
被引用回数：35 パーセンタイル：80.59(Physics, Fluids & Plasmas)ITERのテストブランケットモジュールが作ると思われる誤差磁場の影響を調べる実験をDIII-Dにおいて実施した。プラズマ回転とモードロッキング,閉じ込め,LH遷移,ELM安定化,ELMとHモードペデスタル特性,高エネルギー粒子損失等を調べた。実験では、ITERの1つの赤道面ポートを模擬する3つ組のコイルを1セット使用した。その結果、ITERのTBMが作る誤差磁場のためにITERの運転が妨げられるような結果は得られなかった。一番大きな変化はプラズマ回転を減速させるものであり、非共鳴ブレーキング効果によってプラズマ全体の回転が50%程度減少した。密度や閉じ込めへの影響は、回転の影響の1/3程度である。これらの影響は、プラズマ圧力の高いプラズマや回転の低いプラズマで顕著である。それ以外の影響は軽微であった。
Snipes, J. A.*; Schaffer, M. J.*; Gohil, P.*; de Vries, P.*; Fenstermacher, M. E.*; Evans, T. E.*; Gao, X. M.*; Garofalo, A.*; Gates, D. A.*; Greenfield, C. M.*; et al.
no journal, ,
磁性体で作られているITERのテストブランケットモジュール(TBM)が作る誤差磁場がプラズマ運転と性能へ与える影響を調べる実験をDIII-Dで実施した。ポロイダル磁場とトロイダル磁場を作る一組のコイルをプラズマ近傍の水平ポートに設置した。TBMコイルは、トロイダル磁場リップルとの総和で5.7%という局所磁場リップルを作り出すことが可能で、この値は1.3トンのITER用TBMが作る局所磁場リップルの4倍に相当する。実験では、トロイダル回転の減少はリップルに敏感であるが、閉じ込め性能への影響では、3%以上の局所磁場リップルで15-18%の減少、1.7%以下では影響はほとんど見られないことがわかった。
トカマクプラズマにおけるMHDモードの振舞い松永 剛; 岡林 典男*; 相羽 信行; Boedo, J. A.*; Ferron, J. R.*; Hanson, J. M.*; Hao, G. Z.*; Heidbrink, W. W.*; Holcomb, C. T.*; In, Y.*; et al.
no journal, ,
高運転では高い核融合出力密度を得ることができるため、コンパクトな原型炉が実現可能である。このような核燃焼・高領域では、MHD安定性が臨界安定に近く、かつ高エネルギーイオンが多数存在するためこれらの相互作用が予想される。JT-60U及びDIII-Dの壁なし限界を超える高プラズマにおいて、高エネルギーイオン駆動不安定性が発生し、抵抗性壁モードや周辺局在化モードを誘発する現象を観測した。これらの誘発現象には、高エネルギーイオン駆動不安定性によって増加した高エネルギーイオンの周辺への輸送がこれらの相互作用と関係していると考えられる。本講演ではJT-60UとDIII-Dでの実験結果について詳細に紹介する。
Liang, N.*; Chiang, P.-N.*; Wang, Y.*; 寺本 宗正*; 高木 健太郎*; 近藤 俊明*; 小嵐 淳; Zhang, Y.*; Li, S.*; Fang, J.*; et al.
no journal, ,
Asian terrestrial ecosystems occupy vast areas from tropical forests and wetlands in Southeast Asia to boreal ecosystems in northeastern Asia, and as well as alpine ecosystems on the Tibet Plateau. These ecosystems make a significant contribution to the regional and global carbon budgets. Accurately quantifying CO
/CH
balances is critical for setting targets for their emission reductions and to identify and promote effective mitigation strategies. Since the mid-1990s, we have been installing multichannel automated chamber systems boreal ecosystems in Siberian and Alaska, temperate forests and grassland in East Asia, wetlands and permafrost on the Tibetan Plateau, and subtropical and tropical forests in Southeast Asia, for continuous measurements of forest floor CO budget as well as net ecosystem production. Among the sites, eight ecosystems are using for conducting soil warming experiments. This talk will present CO/CH fluxes and their controls of representative Asian terrestrial ecosystems with the chamber network.
寺本 宗正*; 近藤 俊明*; Liang, N.*; Zeng, J.*; 中根 周歩*; 小嵐 淳; 安藤 麻里子
no journal, ,
Soil respiration is the second largest carbon flux in terrestrial ecosystem, and it consists of soil organic carbon decomposition by microbiota (heterotrophic respiration, Rh) and plant root respiration. Rh corresponds to more than half of soil respiration and increases exponentially along with temperature rise. Therefore, it is possible that global warming increases Rh, and the increased Rh further accelerates global warming (positive feedback). To examine the long-term warming effect on Rh, we set multi-channel automated chamber and artificial warming system in a warm-temperate evergreen broad-leaved forest in Higashi Hiroshima, western Japan. Seasonal changes of CO effluxes in control (Rh) and warmed (Rhw) treatment were largely dependent on soil temperature. However, the influence of soil moisture was also strong during summer period from July to September due to low precipitation. Annual Q
values were ranged from 2.19 to 3.64 in Rh and from 2.11 to 3.57 in Rhw. Stimulatory warming effect on Rh was continuously confirmed over the 10 years of observation. The annual increased ratio of Rh due to soil warming by 1
C (annual warming effect) ranged from 4.2 to 13.5%. There was a marginally significant relationship between summer precipitation and annual warming effect. The result suggested that the annual warming effect was controlled by summer precipitation and resulting soil moisture level in this research site.
寺本 宗正*; 近藤 俊明*; Liang, N.*; Zeng, J.*; 中根 周歩*; 小嵐 淳; 安藤 麻里子
no journal, ,
Globally, soil contains around 3,000 GtC of soil organic carbon (SOC). SOC is decomposed by soil microbiota, and CO is released to the atmosphere (heterotrophic respiration, Rh). Global annual Rh is estimated as 51-57 GtC, and this large CO efflux increases exponentially along with temperature rise. Therefore, it is possible that global warming increases Rh, and the increased Rh further accelerates global warming (positive feedback). To examine the long-term feedback of SOC decomposition to global warming in Asian monsoon forest region, we set multi-channel automated chamber and artificial warming system in a warm-temperate evergreen broad-leaved forest in Higashi Hiroshima, western Japan, in September 2007. Remarkable exponential relationship between soil temperature and soil CO efflux was confirmed each year. However, significant and strong relationship between soil moisture and soil CO efflux was also observed during summer period from July to September. No decreasing trend of stimulatory warming effect on Rh was confirmed over the 10 years of observation. There was a marginally significant relationship between summer precipitation and annual warming effect. This study suggested the relationship between moist environment in Asian monsoon region and the sustained stimulatory soil warming effect on SOC decomposition.
Liang, N.*; Zhang, Y.*; Chiang, P.-N.*; Lai, D.*; 寺本 宗正*; 高木 健太郎*; 近藤 俊明*; 小嵐 淳; Wang, Y.*; Li, S.*; et al.
no journal, ,
Asian terrestrial ecosystems occupy vast areas from tropical forests and wetlands in Southeast Asia to boreal ecosystems in northeastern Asia, and as well as alpine ecosystems on the Tibet Plateau. These ecosystems play important roles in regional and global carbon sink and global warming mitigation. Accurately quantifying CO/CH balances is critical for setting targets for their emission reductions and to identify and promote effective mitigation strategies. Since the mid-1990s, we have been developing an automated chamber network that covers the boreal ecosystems in Siberian and Alaska, temperate forests and grassland in East Asia, wetlands and permafrost on the Tibetan Plateau, and subtropical and tropical forests and wetlands in Southeast Asia, for continuous measurements of CO/CH budget as well as net ecosystem production. Among the sites, ten forests are using for conducting soil warming experiments. This talk will present long-term CO/CH fluxes and their response and feedback to climate change.
寺本 宗正*; Liang, N.*; 高木 健太郎*; 近藤 俊明*; 近藤 俊明*; 小嵐 淳; 安藤 麻里子; 高木 正博*; 石田 祐宣*; 楢本 正明*; et al.
no journal, ,
Soil respiration (Rs) consists of root respiration and heterotrophic respiration (Rh, decomposition of soil organic carbon by soil microbiota). Rh contributes to more than the half of Rs. Because Rh exponentially increases with temperature, it is concerned that increased Rh under future warmer environment might be further accelerate global warming (positive feedback). Therefore, long-term response of Rh to global warming is one of the most important elements for precise prediction for future climate change. Soil warming experiment in field is one of the effective methods to examine the long-term response of Rh against global warming. However, such long-term monitoring data under warmed environment is totally limited, especially in Asian monsoon region. To examine long-term response of Rh in Asian monsoon forest soil, we installed the same multi-channel automated chamber measurement system in typical forests in Asian monsoon region, and we conducted several years of soil warming experiments. In this presentation, we show the long-term response of Rh against artificial soil warming and control factors for the seasonal and inter-annual variation of the warming effect on Rh in those several forest ecosystems.
寺本 宗正*; 近藤 俊明*; Liang, N.*; Zeng, J.*; 中根 周歩*; 小嵐 淳; 安藤 麻里子; 荒巻 能史*; 冨松 元*; Zhao, X.*
no journal, ,
温暖化が土壌有機炭素分解に与える影響を長期的に評価するため、東広島のアラカシ林において自動開閉チャンバーシステムと土壌を温暖化するための赤外線ヒーターを設置して、微生物による土壌有機炭素分解に由来するCOのフラックスを連続的に観測した。温暖化によって増加したCOフラックスの割合(温暖化効果)は、同様の手法によってアジアモンスーン地域の森林において行われた報告よりも相対的に小さかった。これには、本サイトにおける土壌が夏季に乾燥影響を強く受けることが関わっているものと考えられた。しかしながら、欧米における報告とは異なり、約12年の温暖化処理を経ても温暖化効果は低減の傾向を示さなかった。
Liang, N.*; 寺本 宗正*; 高木 健太郎*; 近藤 俊明*; 小嵐 淳; 安藤 麻里子; 平野 高司*; 高橋 善幸*; 高木 正博*; 石田 祐宣*; et al.
no journal, ,
欧米に比べ、有機炭素が豊富な日本を含むアジアモンスーン地域の森林土壌は、微生物呼吸の温暖化に対する長期的なCO排出量増進の応答が大きいことに加え、温暖化に伴う土壌の乾燥化でCH吸収能が上昇する可能性も、土壌の劣化でCH吸収能が低下する可能性も秘めている。しかし、CHを含めた土壌炭素動態の気候変動応答に関わる観測データの欠如は、将来予測の大きな不確実性の一因となっている。そこで本研究では、森林における土壌炭素動態の気候変動影響メカニズムの解明に加え、世界的に前例のない、アジア域を網羅する森林土壌におけるCH吸収能に関する多地点連続観測、広域推定及び将来予測を行う。国立環境研究所が開発した世界最大規模のチャンバー観測ネットワークを活用して、北海道からマレーシアまでの広域トランゼクトに沿って選定した代表的な森林生態系を対象に、観測,分析,モデリングアプリーチ等を融合した研究を展開し、アジア域における超高解像な土壌CH/COフラックスの広域推定と将来予測を目指す。
寺本 宗正*; 近藤 俊明*; Liang, N.*; 小嵐 淳; 安藤 麻里子; Zeng, J.*; Sun, L.*; 中根 周歩*; 荒巻 能史*
no journal, ,
土壌からは多量の二酸化炭素(CO)が土壌呼吸として排出されており、土壌呼吸のうち半分以上は、土壌有機炭素の微生物による分解(微生物呼吸)に起因するものとされる。微生物呼吸は温度の上昇に対して指数関数的に上昇する性質をもつため、地球温暖化によって土壌呼吸および微生物呼吸が増加し、さらに温暖化に拍車をかけるという悪循環が懸念されている。その一方で、土壌はメタン(CH)の吸収源としても機能しているが、土壌CHフラックスへの温暖化影響に関しては、統一的な見解が得られていない。これら土壌炭素フラックス(CO, CH)が、長期的な温暖化条件下でどのように変化するのかは、温暖化の将来予測の観点からも重要である。本講演では、長期的な温暖化が土壌炭素フラックスにおよぼす影響に関し、長期観測に基づく定量的な評価結果を紹介するとともに、その原因となるメカニズムに関しても議論したい。
市井 和仁*; 山貫 緋称*; Liang, N.*; 寺本 宗正*; 高橋 善幸*; Zeng, J.*; 高木 健太郎*; 平野 高司*; 石田 祐宣*; 高木 正博*; et al.
no journal, ,
陸域生態系のCO等のフラックスの推定には、近年はAsiaFluxやFLUXNETなど観測ネットワーク網や衛星リモートセンシングデータの充実により、観測データに基づく推定(データ駆動型(data-driven)の推定)が可能になってきた。一方、「土壌呼吸」に関しては、様々な課題を抱えており、広域推定は十分には実現されていない。国立環境研究所らのグループでは統一された観測手法・データ処理手法によるアジア域のチャンバー連続観測ネットワークを構築しており課題を解決できる可能性がある。そこで、我々は、衛星データと機械学習を用いることで土壌呼吸の広域推定を試みている。まずは、日本を対象にした8観測サイトのデータを用いた解析を進めている。本発表では、(1)AsiaFluxやFLUXNETデータベースと衛星観測データを利用して機械学習法を適用することによるCOフラックス(総一次生産量,生態系CO交換量)推定手法の紹介と、(2)土壌呼吸ネットワークと衛星観測データと機械学習を用いた土壌呼吸の広域推定と既存のデータセットとの比較解析について紹介し、今後の課題についても議論したい。
山貫 緋称*; 市井 和仁*; Liang, N.*; 寺本 宗正*; 高橋 善幸*; Zeng, J.*; 高木 健太郎*; 平野 高司*; 石田 祐宣*; 高木 正博*; et al.
no journal, ,
In this study, we updated our data-driven estimation of soil respiration (SR) across Japan with observation data (eight sites across Japan), remote sensing data (MODIS land products), and random forest regression. Our estimation shows a reasonable performance with R
=0.87 for remote sensing only model and R = 0.91 for remote sensing and in-situ combined model. Based on the established model, we also produced upscaled estimations of SR across Japan with 1km spatial resolution from 2000 to 2020. Intercomparison of our estimation with other available datasets was also conducted to understand advantages of our estimation. Our results show spatially more explicit variations compared with other global products. In addition, our advantage is to capture temporal variations (e.g. 8 days). We also confirmed that previous estimations do not reproduce our observation network datasets, indicating consistent observation approach is important to upscale soil respiration.
