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Comparison of heavy-ion transport simulations; Collision integral with pions and $$Delta$$ resonances in a box

小野 章*; Xu, J.*; Colonna, M.*; Danielewicz, P.*; Ko, C. M.*; Tsang, M. B.*; Wang, Y,-J.*; Wolter, H.*; Zhang, Y.-X.*; Chen, L.-W.*; et al.

Physical Review C, 100(4), p.044617_1 - 044617_35, 2019/10


 被引用回数:29 パーセンタイル:98.33(Physics, Nuclear)



Population of nuclides with Z$$ge$$98 in multi-nucleon transfer reactions of $$^{48}$$Ca+$$^{248}$$Cm

Devaraja, H. M.*; Heinz, S.*; Beliuskina, O.*; Hofmann, S.*; Hornung, C.*; M$"u$nzenberg, G.*; Ackermann, D.*; Gupta, M.*; Gambhir, Y. K.*; Henderson, R. A.*; et al.

European Physical Journal A, 55(2), p.25_1 - 25_9, 2019/02

 被引用回数:6 パーセンタイル:76.03(Physics, Nuclear)

The results for nuclei above curium, produced in multi-nucleon transfer reactions of $$^{48}$$Ca+$$^{248}$$Cm at the velocity filter SHIP of GSI Darmstadt, are presented. Spontaneous fission and $$alpha$$ activities have been used to study the population of nuclei with lifetimes ranging from few milliseconds to several days. We observed several, relatively neutron-rich isotopes with atomic numbers Z $$ge$$ 98; among them a weak 224 millisecond activity which we tentatively attributed to $$^{260}$$No. The measured cross-sections of the observed nuclei give hope that multi-nucleon transfer reactions are a way to reach new neutron-rich heavy and superheavy nuclei, which are not accessible in other reactions. We compare our results with data from earlier experiments and discuss limitations and future perspectives of the method.


ETSON-MITHYGENE benchmark on simulations of upward flame propagation experiment in the ENACCEF2 experimental facility

Bentaib, A.*; Chaumeix, N.*; Grosseuvres, R.*; Bleyer, A.*; Gastaldo, L.*; Maas, L.*; Jallais, S.*; Vyazmina, E.*; Kudriakov, S.*; Studer, E.*; et al.

Proceedings of 12th International Topical Meeting on Nuclear Reactor Thermal-Hydraulics, Operation and Safety (NUTHOS-12) (USB Flash Drive), 11 Pages, 2018/10

In the framework of the French MITHYGENE project, the new highly instrumented ENACCEF2 facility was built at the Institut de Combustion Aerothermique Reactivite et Environnement (ICARE) of the Centre National de la Recherche Scientifique (CNRS) in Orleans (France) to address the flame propagation in hydrogen combustion during a severe accident. The ENACCEF2 facility is a vertical tube of 7.65 m height and 0.23 m inner diameter. In the lower part of the tube, annular obstacles are installed to promote turbulent flame propagation. At the initiative of the MITHYGENE project consortium and the European Technical Safety Organisation Network (ETSON), a benchmark on hydrogen combustion was organised with the goal to identify the current level of the computational tools in the area of hydrogen combustion simulation under conditions typical for safety considerations for NPP. In the proposed paper, the simulation results obtained by participating organizations, using both Computational Fluid Dynamics (CFD) and lumped-parameter computer codes, are compared to experimental results and analysed.


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

Zhang, Y.-X.*; Wang, Y,-J.*; Colonna, M.*; Danielewicz, P.*; 小野 章*; 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

 被引用回数:63 パーセンタイル:99.37(Physics, Nuclear)

2017年4月に開催された国際会議Transport2017において、重イオン核反応モデルの国際的な比較が議論された。重イオン加速器の安全評価や宇宙飛行士の被ばく評価等で重要な役割を果たすため、世界中で重イオン核反応の様々な理論モデルが開発されている。本研究はモデル間の共通点と差異を明らかにし、各モデルの問題点を明らかにした。比較において、辺の長さが20fmの直方体に320個の中性子と320個の陽子をランダム配置し、それらが時間発展に伴って起こす散乱の回数や散乱時のエネルギーなどを計算する条件が設定された。また、結果以外にも、理論モデルを構成するアルゴリズムについても比較を行った。発表者は重イオン核反応モデルJQMD(JAERI Quantum Molecular Dynamics)を用いて計算を行い、世界で開発されている15の計算コードによる計算結果と比較した。コードアルゴリズムの比較では、JQMDは必ず陽子から 優先的に衝突確率を計算し、その後に中性子の衝突を計算するため、物理描像の妥当性が指摘された。一方、JQMDは他のモデルとほぼ同じ計算結果を出すことも判明した。衝突回数や運動量の計算値が平均から2倍以上乖離するモデルもある中で、JQMDは本計算条件で安定した性能を発揮することが確認された。


Corrosion test of HTGR graphite with SiC coating

Chikhray, Y.*; Kulsartov, T.*; Shestakov, V.*; Kenzhina, I.*; Askerbekov, S.*; 角田 淳弥; 植田 祥平; 柴田 大受; 坂場 成昭; Abdullin, Kh.*; et al.

Proceedings of 8th International Topical Meeting on High Temperature Reactor Technology (HTR 2016) (CD-ROM), p.572 - 577, 2016/11



Observation of new neutron-deficient isotopes with Z$$ge$$92 in multinucleon transfer reactions

Devaraja, H. M.*; Heinz, S.*; Beliuskina, O.*; Comas, V. F.*; Hofmann, S.*; Hornung, C.*; M$"u$nzenberg, G.*; 西尾 勝久; Ackermann, D.*; Gambhir, Y. K.*; et al.

Physics Letters B, 748, p.199 - 203, 2015/09


 被引用回数:50 パーセンタイル:96.89(Astronomy & Astrophysics)

In deep inelastic multinucleon transfer reactions of $$^{48}$$Ca +$$^{248}$$Cm we observed about 100 residual nuclei with proton numbers between Z =82 and Z =100. Among them, there are five new neutron-deficient isotopes: $$^{216}$$U, $$^{219}$$Np, $$^{223}$$Am, $$^{229}$$Am and $$^{233}$$Bk. As separator for the transfer products we used the velocity filter SHIP of GSI while the isotope identification was performed via the $$alpha$$-decay chains of the nuclei. These first results reveal that multinucleon transfer reactions together with here applied fast and sensitive separation and detection techniques are promising for the synthesis of new isotopes in the region of heaviest nuclei.


Assessment of operational space for long-pulse scenarios in ITER

Polevoi, A. R.*; Loarte, A.*; 林 伸彦; Kim, H. S.*; Kim, S. H.*; Koechl, F.*; Kukushkin, A. S.*; Leonov, V. M.*; Medvedev, S. Yu.*; 村上 匡且*; et al.

Nuclear Fusion, 55(6), p.063019_1 - 063019_8, 2015/05

 被引用回数:28 パーセンタイル:87.19(Physics, Fluids & Plasmas)

The operational space ($$I_p$$-$$n$$) for long pulse scenarios of ITER was assessed by 1.5D core transport modelling with pedestal parameters predicted by the EPED1 code. The analyses include the majority of transport models presently used for interpretation of experiments and ITER predictions. The EPED1 code was modified to take into account boundary conditions predicted by SOLPS for ITER. In contrast with standard EPED1 assumptions, EPED1 with the SOLPS boundary conditions predicts no degradation of the pedestal pressure as density is reduced. Lowering the plasma density to $$n_e sim$$ 5-6 $$times$$ 10$$^{19}$$ m$$^{-3}$$ leads to an increased plasma temperature (similar pedestal pressure), which reduces the loop voltage and increases the duration of the burn phase to $$Delta t_{rm burn} sim$$ 1000 s with Q $$ge$$ 5 for $$I_p ge$$ 13 MA at moderate normalised pressure ($$beta_N sim$$ 2). These ITER plasmas require the same level of additional heating power as the reference Q = 10 inductive scenario at 15 MA. However, unlike the "hybrid" scenarios considered previously, these H-mode plasmas do not require specially shaped q profiles nor improved confinement in the core for the transport models considered in this study. Thus, these medium density H-mode plasma scenarios with $$I_p ge$$ 13 MA present an attractive alternative to hybrid scenarios to achieve ITER's long pulse Q $$ge$$ 5 and deserve further analysis and experimental demonstration in present tokamaks.


High order harmonics from relativistic electron spikes

Pirozhkov, A. S.; 神門 正城; Esirkepov, T. Z.; Faenov, A. Y.*; Pikuz, T. A.*; 河内 哲哉; 匂坂 明人; Koga, J. K.; 森 道昭; 川瀬 啓悟*; et al.

RAL-TR-2015-025, P. 22, 2015/00

We provide a description of experiments performed with the J-KAREN and Astra Gemini lasers where we discovered a new regime of relativistic high-order harmonic generation by multi-terawatt femtosecond lasers in gas targets. The results were explained using particle-in-cell simulations and catastrophe theory. Our work paves the way towards a bright coherent X-ray source based on compact lasers and accessible, repetitive, and debris-free gas jet targets. Such a source will be crucial for fundamental research and numerous applications requiring pumping, probing, imaging of microscopic objects and for attosecond science.


Characteristics of global energy confinement in KSTAR L- and H-mode plasmas

Kim, H.-S.*; Jeon, Y. M.*; Na, Y.-S.*; Ghim, Y.-C.*; Ahn, J.-W.*; Yoon, S. W.*; Bak, J. G.*; Bae, Y. S.*; Kim, J. S.*; Joung, M.*; et al.

Nuclear Fusion, 54(8), p.083012_1 - 083012_11, 2014/08

 被引用回数:4 パーセンタイル:24.21(Physics, Fluids & Plasmas)



Development of advanced inductive scenarios for ITER

Luce, T. C.*; Challis, C. D.*; 井手 俊介; Joffrin, E.*; 鎌田 裕; Politzer, P. A.*; Schweinzer, J.*; Sips, A. C. C.*; Stober, J.*; Giruzzi, G.*; et al.

Nuclear Fusion, 54(1), p.013015_1 - 013015_15, 2013/12

 被引用回数:23 パーセンタイル:80.5(Physics, Fluids & Plasmas)

The ITPA IOS group has coordinated experimental and modeling activity on the development of advanced inductive scenarios for applications in the ITER tokamak. This report documents the present status of the physics basis and the prospects for applications in ITER. The key findings are: (1) inductive scenarios capable of higher $$beta_{rm N} ge 2.4$$ than the ITER baseline scenario ($$beta_{rm N} = 1.8$$) with normalized confinement at or above the standard H-mode scaling have been established under stationary conditions on the four largest diverted tokamaks (AUG, DIII-D, JET, JT-60U) in a broad range in $$q_{rm 95}$$ and density; (2) MHD modes can play a key role in reaching stationary high performance, but also define the stability and confinement limits; (3) the experiments have yielded clearer measurements of the normalized gyroradius scalin; and (4) coordinated modeling activity supports the present research by clarifying the most significant uncertainties in the projections to ITER.


Optimization of ITER operational space for long-pulse scenarios

Polevoi, A. R.*; 林 伸彦; Kim, H. S.*; Kim, S. H.*; Koechl, F.*; Kukushkin, A. S.*; Leonov, V. M.*; Loarte, A.*; Medvedev, S. Yu.*; 村上 匡且*; et al.

Europhysics Conference Abstracts (Internet), 37D, p.P2.135_1 - P2.135_4, 2013/07

Long-pulse operation $$Delta t sim$$ 1000 s with $$Q ge$$ 5 is foreseen in ITER to demonstrate high neutron fluence scenarios which can be of use for the nuclear technology and for the TBM. In this study we address the viability of achieving ITER's long-pulse scenario in plasma regimes with H-mode confinement level by characterizing the current-density operational space and the achievable Q with long pulse burning phases. The EPED1 model with boundary conditions from SOLPS predicts no degradation of pedestal pressure with decreasing density in ITER. Modelling of core transport with 1.5D transport models carried out with pedestal parameters predicted by EPED1+SOLPS indicate that there is a large operational space for long pulse plasma operation with high fusion gain $$Q ge$$ 5. Reducing the plasma density to $$n_e sim$$ 5-6 10$$^{19}$$m$$^{-3}$$ leads to an increased plasma temperature (similar pedestal pressure) which reduces the loop voltage and increases the duration of the burn phase to $$Delta t sim$$ 1000 s with $$Q ge$$ 5 for $$I_p ge$$ 13 MA at moderate normalised pressure, $$beta_N sim$$ 2. Unlike the "hybrid" scenarios, these H-mode plasmas do not require specially shaped q profiles nor improved confinement in the core for the majority of the transport models considered in this study. Thus, these medium density H-mode plasma scenarios present an attractive alternative to hybrid scenarios to achieve ITER's long pulse.


Characteristics of the first H-mode discharges in KSTAR

Yoon, S. W.*; Ahn, J.-W.*; Jeon, Y. M.*; 鈴木 隆博; Hahn, S. H.*; Ko, W. H.*; Lee, K. D.*; Chung, J. I.*; Nam, Y. U.*; Kim, J.*; et al.

Nuclear Fusion, 51(11), p.113009_1 - 113009_9, 2011/11

 被引用回数:25 パーセンタイル:75.77(Physics, Fluids & Plasmas)

中性粒子ビーム(NB)と電子サイクロトロン(EC)加熱を組合せることでKSTARトカマクにおいてELMを有する典型的なHモード放電を得た。2Tのトロイダル磁場では、Hモード遷移に必要な閾パワーは最小で1.1MWであり密度は1.4$$times$$10$$^{19}$$ m$$^{-3}$$であった。この密度以下では閾パワーは増加した。閉じ込め時間はスケーリング則より1.4-1.6倍高いが、NBの損失を考慮するとスケーリング則に近づく。Hモード時には電子温度とイオン温度がペデスタル部で明確に上昇したが、中心部のイオン温度は大きくは変化しなかった。他方、トロイダル回転はHモード時に全領域で増加した。ELM周波数は30-50HzでELM時の蓄積エネルギーの変化割合は5%以下であった。NBとEC加熱を組合せた場合には、大振幅のELM間に小振幅のELMが観測された。


Event structure and double helicity asymmetry in jet production from polarized $$p + p$$ collisions at $$sqrt{s}$$ = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review D, 84(1), p.012006_1 - 012006_18, 2011/07

 被引用回数:25 パーセンタイル:72.31(Astronomy & Astrophysics)

重心エネルギー200GeVでの縦偏極陽子陽子衝突からのジェット生成のイベント構造と二重非対称($$A_{LL}$$)について報告する。光子と荷電粒子がPHENIX実験で測定され、イベント構造がPHYTIAイベント生成コードの結果と比較された。再構成されたジェットの生成率は2次までの摂動QCDの計算で十分再現される。測定された$$A_{LL}$$は、一番低い横運動量で-0.0014$$pm$$0.0037、一番高い横運動量で-0.0181$$pm$$0.0282であった。この$$A_{LL}$$の結果を幾つかの$$Delta G(x)$$の分布を仮定した理論予想と比較する。


Identified charged hadron production in $$p + p$$ collisions at $$sqrt{s}$$ = 200 and 62.4 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; 秋葉 康之*; Al-Bataineh, H.*; Alexander, J.*; 青木 和也*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06

 被引用回数:156 パーセンタイル:99.42(Physics, Nuclear)

200GeVと62.4GeVでの陽子陽子の中心衝突からの$$pi, K, p$$の横運動量分布及び収量をRHICのPHENIX実験によって測定した。それぞれエネルギーでの逆スロープパラメーター、平均横運動量及び単位rapidityあたりの収量を求め、異なるエネルギーでの他の測定結果と比較する。また$$m_T$$$$x_T$$スケーリングのようなスケーリングについて示して陽子陽子衝突における粒子生成メカニズムについて議論する。さらに測定したスペクトルを二次の摂動QCDの計算と比較する。


Azimuthal correlations of electrons from heavy-flavor decay with hadrons in $$p+p$$ and Au+Au collisions at $$sqrt{s_{NN}}$$ = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; 秋葉 康之*; Al-Bataineh, H.*; Alexander, J.*; 青木 和也*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

 被引用回数:8 パーセンタイル:52.71(Physics, Nuclear)



Measurement of neutral mesons in $$p$$ + $$p$$ collisions at $$sqrt{s}$$ = 200 GeV and scaling properties of hadron production

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review D, 83(5), p.052004_1 - 052004_26, 2011/03

 被引用回数:149 パーセンタイル:98.49(Astronomy & Astrophysics)

RHIC-PHENIX実験で重心エネルギー200GeVの陽子陽子衝突からの$$K^0_s$$, $$omega$$, $$eta'$$$$phi$$中間子生成の微分断面積を測定した。これらハドロンの横運動量分布のスペクトルの形はたった二つのパラメーター、$$n, T$$、のTsallis分布関数でよく記述できる。これらのパラメーターはそれぞれ高い横運動量と低い横運動量の領域のスペクトルを決めている。これらの分布をフィットして得られた積分された不変断面積はこれまで測定されたデータ及び統計モデルの予言と一致している。


Integrated modeling of steady-state scenarios and heating and current drive mixes for ITER

村上 和功*; Park, J. M.*; Giruzzi, G.*; Garcia, J.*; Bonoli, P.*; Budny, R. V.*; Doyle, E. J.*; 福山 淳*; 林 伸彦; 本多 充; et al.

Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 8 Pages, 2011/03

Recent progress on ITER steady-state scenario modeling by the ITPA-IOS group is reviewed. Code-to-code benchmarks as the IOS group's common activities for the two steady-state scenarios (weak shear scenario and internal transport barrier scenario) are reviewed. These are discussed in terms of transport and kinetic profiles, heating and CD sources using various transport codes.


OECD/NEA expert group on uncertainty analysis for criticality safety assessment; Current activities

Ivanova, T.*; Fernex, F.*; Kolbe, E.*; Vasiliev, A.*; Lee, G. S.*; Woo, S. W.*; Mennerdahl, D.*; 長家 康展; Neuber, J. C.*; Hoefer, A.*; et al.

Proceedings of International Conference on Physics of Reactors; Advances in Reactor Physics to Power the Nuclear Renaissance (PHYSOR 2010) (CD-ROM), 15 Pages, 2010/05



Status of KSTAR electron cyclotron heating system

Bae, Y. S.*; Na, Y. S.*; Oh, Y. K.*; Kwon, M.*; Bak, J. S.*; Lee, G. S.*; Jeong, J. H.*; Park, S. I.*; Cho, M. H.*; Namkung, W.*; et al.

Fusion Science and Technology, 52(2), p.321 - 333, 2007/08

 被引用回数:21 パーセンタイル:81.84(Nuclear Science & Technology)

84GHz, KSTAR電子サイクロトロン波加熱システムにおいてジャイロトロンの実験を開始し、これまでに20$$mu$$secのパルス発振に成功した。また、入射アンテナ(ランチャー)を設計製作し、KSTAR装置に取り付けプラズマ実験が行える状況にある。また、ITERを想定したNTM制御あるいは内部輸送障壁生成を目的とした170GHz電子サイクロトロン波加熱システム開発を行っているが、原子力機構がITER用に開発した170GHz, 1MWジャイロトロンを設置する予定となっている。本論文では、KSTARにおける84GHz及び170GHzジャイロトロンシステム開発を述べるとともに、それらを利用した電流駆動やXモード入射についても議論する。


The H-mode pedestal, ELMs and TF ripple effects in JT-60U/JET dimensionless identity experiments

Saibene, G.*; 大山 直幸; L$"o$nnroth, J.*; Andrew, Y.*; la Luna, E. de.*; Giroud, C.*; Huysmans, G. T. A.*; 鎌田 裕; Kempenaars, M. A. H.*; Loarte, A.*; et al.

Nuclear Fusion, 47(8), p.969 - 983, 2007/08

 被引用回数:30 パーセンタイル:73.38(Physics, Fluids & Plasmas)


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