Development of a control system for core-sampling USV that combines sliding mode control and neural network

森戸 誠*; 藤井 俊*; 吉村 洸貴*; 眞田 幸尚; 馬場 尚一郎*; 松永 浩志*; Mori, Takami*; 佐藤 憲一郎*; 田原 淳一郎*

Proceedings of 34th International Ocean and Polar Engineering Conference (ISOPE-2024), p.3754 - 3761, 2024/06

本研究では、海底地盤の放射線計測を行う無人探査機の制御手法として、スライディングモード制御とニューラルネットワークを組み合わせた手法を提案する。制御入力のベースとしてスライディングモード制御を用い、スライディングモード制御のパラメータの一つであるとその変化率が小さくなるようにニューラルネットワークコントローラを用いて補正入力を加える。本方式を用いた制御システムを製作した後、シミュレーション試験、海域試験を行い、本方式による調査が可能かどうかを評価した。

Intruder configurations in Ne at the transition into the island of inversion; Detailed structure study of Ne

Wang, H.*; 安田 昌弘*; 近藤 洋介*; 中村 隆司*; Tostevin, J. A.*; 緒方 一介*; 大塚 孝治*; Poves, A.*; 清水 則孝*; 吉田 数貴; et al.

Physics Letters B, 843, p.138038_1 - 138038_9, 2023/08

https://doi.org/10.1016/j.physletb.2023.138038

Neからの1中性子除去反応を用いて、Neの詳細な線分光を行った。平行運動量分布の解析に基づき、Neの準位構造とスピンパリティを決定し、初めて負のパリティ状態を同定した。測定された断面積と運動量分布から、N=20とN=28のシェルギャップの消失の証拠となる有意なintruder p-wave強度が明らかになった。束縛状態については、弱いf-waveの可能性のある強度が観測された。いくつかの有効相互作用を用いた大規模殻模型計算では、実験的に観測された大きなp-wave強度と小さなf-wave強度は再現されず、Ne同位体に沿った反転の島への遷移の完全な理論的記述への挑戦が続いていることを示している。

Development plan for coupling technology between high temperature gas-cooled reactor HTTR and Hydrogen Production Facility, 2; Development plan for coupling equipment between HTTR and Hydrogen Production Facility

水田 直紀; 守田 圭介; 青木 健; 沖田 将一朗; 石井 克典; 倉林 薫; 安田 貴則; 田中 真人; 井坂 和義; 野口 弘喜; et al.

Proceedings of 30th International Conference on Nuclear Engineering (ICONE30) (Internet), 6 Pages, 2023/05

High temperature gas-cooled reactor (HTGR) is expected to extend the use of nuclear heat to a wider spectrum of industrial applications such as hydrogen production, high efficiency power generation, etc., due largely to high temperature heat supply capability as well as inherent safe characteristics. Japan Atomic Energy Agency (JAEA) have been contracted by the Agency for Natural Resources and Energy, part of the Ministry of Economy, Trade and Industry (METI) of Japan, to conduct its Hydrogen Production Demonstration Project Utilizing Very High Temperature. The primary objective of this project is to establish "coupling technology" between HTGR and hydrogen production facility in accordance with "Green Growth Strategy Through Achieving Carbon Neutrality in 2050". From this fiscal year, JAEA initiated a program to produce hydrogen using an HTTR (High Temperature Engineering Test Reactor) to develop coupling technologies between HTGR and hydrogen production facility required for a massive, cost-effective and carbon-free hydrogen production technology. This paper describes the development plan for coupling equipment which is required for an HTTR heat application test as coupling technologies between an HTTR and a hydrogen production facility. The coupling equipment is composed of a high temperature isolation valve to prevent the ingress of the flammable gas and/or the leakage of radioactive materials for nuclear facility, a secondary helium gas circulator to feed a high temperature helium gas, and a high temperature insulation pipe to transport of a high temperature helium gas from an Internal Heat Exchanger (IHX) to a hydrogen production facility. The development plan of coupling equipment contains each target and draft schedule.

Japanese Evaluated Nuclear Data Library version 5; JENDL-5

岩本 修; 岩本 信之; 国枝 賢; 湊 太志; 中山 梓介; 安部 豊*; 椿原 康介*; 奥村 森*; 石塚 知香子*; 吉田 正*; et al.

Journal of Nuclear Science and Technology, 60(1), p.1 - 60, 2023/01

https://doi.org/10.1080/00223131.2022.2141903

The fifth version of Japanese Evaluated Nuclear Data Library, JENDL-5, was developed. JENDL-5 aimed to meet a variety of needs not only from nuclear reactors but also from other applications such as accelerators. Most of the JENDL special purpose files published so far were integrated into JENDL-5 with revisions. JENDL-5 consists of 11 sublibraries: (1) Neutron, (2) Thermal scattering law, (3) Fission product yield, (4) Decay data, (5) Proton, (6) Deuteron, (7) Alpha-particle, (8) Photonuclear, (9) Photo-atomic, (10) Electro-atomic, and (11) Atomic relaxation. The neutron reaction data for a large number of nuclei in JENDL-4.0 were updated ranging from light to heavy ones, including major and minor actinides which affect nuclear reactor calculations. In addition, the number of nuclei of neutron reaction data stored in JENDL-5 was largely increased; the neutron data covered not only all of naturally existing nuclei but also their neighbor ones with half-lives longer than 1 day. JENDL-5 included the originally evaluated data of thermal scattering law and fission product yield for the first time. Light charged-particle and photon induced reaction data were also included for the first time as the JENDL general purpose file.

Recent progress and future prospects of hyperon nucleon scattering experiment

三輪 浩司*; 藤田 真奈美; 原田 健志; 長谷川 勝一; 細見 健二; 市川 真也; 今井 憲一*; 佐甲 博之; 佐藤 進; 田村 裕和; et al.

EPJ Web of Conferences, 271, p.04001_1 - 04001_7, 2022/11

https://doi.org/10.1051/epjconf/202227104001

A new hyperon-proton scattering experiment, dubbed J-PARC E40, was performed to measure differential cross sections of the , elastic scatterings and the scattering by identifying a lot of particles in the momentum ranging from 0.4 to 0.8 GeV/ produced by the reactions. We successfully measured the differential cross sections of these three channels with a drastically improved accuracy with a fine angular step. These new data will become important experimental constraints to improve the theories of the two-body baryon-baryon interactions. Following this success, we proposed a new experiment to measure the differential cross sections and spin observables by using a highly polarized beam for providing quantitative information on the interaction. The results of three channels and future prospects of the scattering experiment are described.

HTTR-熱利用試験専門委員会資料集

青木 健; 清水 厚志; 飯垣 和彦; 沖田 将一朗; 長谷川 武史; 水田 直紀; 佐藤 博之; 坂場 成昭

JAEA-Review 2022-016, 193 Pages, 2022/08

JAEA-Review-2022-016.pdf:42.06MB

日本原子力研究開発機構では、高温ガス炉による大量かつ安価なカーボンフリー水素製造技術の実用化を目指し、世界最高の原子炉出口冷却材温度950Cを記録した高温工学試験研究炉(HTTR)を用いて水素製造を行うHTTR-熱利用試験を計画している。HTTR-熱利用試験では、原子力規制委員会からの設置許可取得を通じて、高温ガス炉と水素製造施設の接続に関し、高い安全性を実現する安全設計を確立することが求められている。しかしながら、これまでに原子炉に水素製造施設を接続した例は世界にまだなく、我が国唯一の高温ガス炉であるHTTRを含め、既存の原子力施設を対象とした安全設計ではこのようなシステムを想定していない。そこで、高温ガス炉研究開発センターの下に設置した「HTTR-熱利用試験専門委員会」では、原子力規制委員会による新規制基準への適合性審査に合格したHTTR安全設計をベースに、施設の変更や水素製造施設の接続に伴い安全設計上新たに考慮すべき事象に対する対策を考慮し、HTTR-熱利用試験施設の安全設計案の検討を行った。本稿は、HTTR-熱利用試験専門委員会の技術報告資料や委員コメントとその回答、議事録を取りまとめた。

meson production in Al, Au, Au, and HeAu collisions at GeV

Acharya, U. A.*; 長谷川 勝一; 今井 憲一*; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他365名*

Physical Review C, 106(1), p.014908_1 - 014908_13, 2022/07

https://doi.org/10.1103/PhysRevC.106.014908

Small nuclear collisions are mainly sensitive to cold-nuclear-matter effects; however, the collective behavior observed in these collisions shows a hint of hot-nuclear-matter effects. The identified-particle spectra, especially the mesons which contain strange and antistrange quarks and have a relatively small hadronic-interaction cross section, are a good tool to study these effects. The PHENIX experiment has measured mesons in a specific set of small collision systems Al, Au, and HeAu, as well as Au, at GeV. The transverse-momentum spectra and nuclear-modification factors are presented and compared to theoretical-model predictions. The comparisons with different calculations suggest that quark-gluon plasma may be formed in these small collision systems at GeV. However, the volume and the lifetime of the produced medium may be insufficient for observing strangeness-enhancement and jet-quenching effects. Comparison with calculations suggests that the main production mechanisms of mesons at midrapidity may be different in Al versus HeAu collisions at GeV. While thermal quark recombination seems to dominate in HeAu collisions, fragmentation seems to be the main production mechanism in Al collisions.

Systematic study of nuclear effects in Al, Au, Au, and HeAu collisions at GeV using production

Acharya, U. A.*; 長谷川 勝一; 今井 憲一*; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他547名*

Physical Review C, 105(6), p.064902_1 - 064902_19, 2022/06

https://doi.org/10.1103/PhysRevC.105.064902

The PHENIX collaboration presents a systematic study of production from , Al, Au, Au, and HeAu collisions at GeV. Measurements were performed with different centrality selections as well as the total inelastic, 0% - 100%, selection for all collision systems. For 0% - 100% collisions, the nuclear modification factors, , are consistent with unity for above 8 GeV/, but exhibit an enhancement in peripheral collisions and a suppression in central collisions. The enhancement and suppression characteristics are similar for all systems for the same centrality class. It is shown that for high-- production, the nucleons in the and He interact mostly independently with the Au nucleus and that the counter intuitive centrality dependence is likely due to a physical correlation between multiplicity and the presence of a hard scattering process. These observations disfavor models where parton energy loss has a significant contribution to nuclear modifications in small systems. Nuclear modifications at lower resemble the Cronin effect - an increase followed by a peak in central or inelastic collisions and a plateau in peripheral collisions. The peak height has a characteristic ordering by system size as Au Au HeAu Al. For collisions with Au ions, current calculations based on initial state cold nuclear matter effects result in the opposite order, suggesting the presence of other contributions to nuclear modifications, in particular at lower .

Kinematic dependence of azimuthal anisotropies in Au, Au, and He+Au at = 200 GeV

Acharya, U. A.*; 長谷川 勝一; 今井 憲一*; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他378名*

Physical Review C, 105(2), p.024901_1 - 024901_13, 2022/02

https://doi.org/10.1103/PhysRevC.105.024901

There is strong evidence for the formation of small droplets of quark-gluon plasma in He+Au collisions at the Relativistic Heavy Ion Collider (RHIC) and in +/Pb collisions at the Large Hadron Collider. In particular, the analysis of data at RHIC for different geometries obtained by varying the projectile size and shape has proven insightful. In the present analysis, we find excellent agreement with the previously published PHENIX at RHIC results on elliptical and triangular flow with an independent analysis via the two-particle correlation method, which has quite different systematic uncertainties and an independent code base. In addition, the results are extended to other detector combinations with different kinematic (pseudorapidity) coverage. These results provide additional constraints on contributions from nonflow and longitudinal decorrelations.

Transverse single spin asymmetries of forward neutrons in , Al, and Au collisions at = 200 GeV as a function of transverse and longitudinal momenta

Acharya, U. A.*; 長谷川 勝一; 今井 憲一*; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他305名*

Physical Review D, 105(3), p.032004_1 - 032004_13, 2022/02

https://doi.org/10.1103/PhysRevD.105.032004

In 2015 the PHENIX collaboration at the Relativistic Heavy Ion Collider recorded , Al, and Au collision data at center of mass energies of GeV with the proton beam(s) transversely polarized. At very forward rapidities relative to the polarized proton beam, neutrons were detected either inclusively or in (anti)correlation with detector activity related to hard collisions. The resulting single spin asymmetries, that were previously reported, have now been extracted as a function of the transverse momentum of the neutron as well as its longitudinal momentum fraction . The explicit kinematic dependence, combined with the correlation information allows for a closer look at the interplay of different mechanisms suggested to describe these asymmetries, such as hadronic interactions or electromagnetic interactions in ultra-peripheral collisions, UPC. Events that are correlated with a hard collision indeed display a mostly negative asymmetry that increases in magnitude as a function of transverse momentum with only little dependence on . In contrast, events that are not likely to have emerged from a hard collision display positive asymmetries for the nuclear collisions with a kinematic dependence that resembles that of a UPC based model. Because the UPC interaction depends strongly on the charge of the nucleus, those effects are very small for collisions, moderate for Al collisions, and large for Au collisions.