arXiv - PHYS - Plasma Physics最新文献_第6页

Machine Learning Applications to Computational Plasma Physics and Reduced-Order Plasma Modeling: A Perspective 机器学习在计算等离子体物理和降序等离子体建模中的应用：透视

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-04 DOI: arxiv-2409.02349

Farbod Faraji, Maryam Reza

{"title":"Machine Learning Applications to Computational Plasma Physics and Reduced-Order Plasma Modeling: A Perspective","authors":"Farbod Faraji, Maryam Reza","doi":"arxiv-2409.02349","DOIUrl":"https://doi.org/arxiv-2409.02349","url":null,"abstract":"Machine learning (ML) provides a broad spectrum of tools and architectures\u0000that enable the transformation of data from simulations and experiments into\u0000useful and explainable science, thereby augmenting domain knowledge.\u0000Furthermore, ML-enhanced numerical modelling can revamp scientific computing\u0000for real-world complex engineering systems, creating unique opportunities to\u0000examine the operation of the technologies in detail and automate their\u0000optimization and control. In recent years, ML applications have seen\u0000significant growth across various scientific domains, particularly in fluid\u0000mechanics, where ML has shown great promise in enhancing computational modeling\u0000of fluid flows. In contrast, ML applications in numerical plasma physics\u0000research remain relatively limited in scope and extent. Despite this, the close\u0000relationship between fluid mechanics and plasma physics presents a valuable\u0000opportunity to create a roadmap for transferring ML advances in fluid flow\u0000modeling to computational plasma physics. This Perspective aims to outline such\u0000a roadmap. We begin by discussing some general fundamental aspects of ML,\u0000including the various categories of ML algorithms and the different types of\u0000problems that can be solved with the help of ML. With regard to each problem\u0000type, we then present specific examples from the use of ML in computational\u0000fluid dynamics, reviewing several insightful prior efforts. We also review\u0000recent ML applications in plasma physics for each problem type. The paper\u0000discusses promising future directions and development pathways for ML in plasma\u0000modelling within the different application areas. Additionally, we point out\u0000prominent challenges that must be addressed to realize ML's full potential in\u0000computational plasma physics, including the need for cost-effective\u0000high-fidelity simulation tools for extensive data generation.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The role of non-linear Landau damping for cosmic-ray transport 非线性朗道阻尼对宇宙射线传输的作用

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.02230

Benedikt Schroer, Damiano Caprioli, Pasquale Blasi

引用次数: 0

Relaxation to universal non-Maxwellian equilibria in a collisionless plasma 在无碰撞等离子体中弛豫到普遍的非麦克斯韦平衡状态

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.01742

Robert J. Ewart, Michael L. Nastac, Pablo J. Bilbao, Thales Silva, Luís O. Silva, Alexander A. Schekochihin

引用次数: 0

Saturation of magnetised plasma turbulence by propagating zonal flows 磁化等离子体湍流的饱和传播带流

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.02283

Richard Nies, Felix Parra, Michael Barnes, Noah Mandell, William Dorland

引用次数: 0

Embedding theory contributions to average atom models for warm dense matter 嵌入理论对暖致密物质平均原子模型的贡献

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.02105

Sameen Yunus, David A. Strubbe

{"title":"Embedding theory contributions to average atom models for warm dense matter","authors":"Sameen Yunus, David A. Strubbe","doi":"arxiv-2409.02105","DOIUrl":"https://doi.org/arxiv-2409.02105","url":null,"abstract":"Accurate modeling in the warm dense matter regime is a persistent challenge\u0000with the most detailed models such as quantum molecular dynamics and path\u0000integral Monte Carlo being immensely computationally expensive. Density\u0000functional theory (DFT)-based average atom models (AAM) offer significant\u0000speed-ups in calculation times while still retaining fair accuracy in\u0000evaluating equations of state, mean ionizations, and more. Despite their\u0000success, AAMs struggle to precisely account for electronic interactions -- in\u0000particular, they do not account for effects on the kinetic energy arising from\u0000overlaps in neighboring atom densities. We aim to enhance these models by\u0000including such interactions via the non-additive kinetic potential $v^{rm\u0000nadd}$ as in DFT embedding theories. $v^{rm nadd}$ can be computed using\u0000Thomas-Fermi, von Weizs\"acker, or more sophisticated kinetic energy\u0000functionals. The proposed model introduces $v^{rm nadd}$ as a novel\u0000interaction term in existing ion-correlation models, which include interactions\u0000beyond the central atom. We have applied this model to hydrogen at 5 eV and\u0000densities ranging 0.008 to 0.8 g/cm$^3$, and investigated the effects of\u0000$v^{rm nadd}$ on electron densities, Kohn-Sham energy level shifts, mean\u0000ionization, and total energies.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"94 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Radiative hydrodynamic equations with nonequilibrium radiative transfer 非平衡辐射传递的辐射流体力学方程

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.01827

Mingyu Quan, Xiaojian Yang, Yufeng Wei, Kun Xu

引用次数: 0

Approaching the Lower Temporal Limit of Laser-Produced Plasma Sources for Table-Top Soft X-ray NEXAFS Measurements 接近用于桌面软 X 射线 NEXAFS 测量的激光产生等离子体源的时间下限

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.02280

Danika Nimlos, Alejandro Arellano, Scott Kevin Cushing

{"title":"Approaching the Lower Temporal Limit of Laser-Produced Plasma Sources for Table-Top Soft X-ray NEXAFS Measurements","authors":"Danika Nimlos, Alejandro Arellano, Scott Kevin Cushing","doi":"arxiv-2409.02280","DOIUrl":"https://doi.org/arxiv-2409.02280","url":null,"abstract":"The increasing popularity of time-resolved X-ray absorption measurements for\u0000understanding dynamics in molecular and material systems has led to many\u0000advances in table-top sources for pulsed X-rays. We report on a table top\u0000laser-produced plasma (LPP) source that can perform soft X-ray (SXR), near edge\u0000X-ray absorption fine structure (NEXAFS) measurements using a laser source with\u000023 ps pulse duration. The spectrometer's key specifications, such as\u0000brilliance, resolution, and stability, are characterized against the more\u0000commonly used longer-pulse-duration LPP sources. The 23 ps laser produced\u0000approximately an order of magnitude weaker SXR flux than the 8 ns laser for a\u0000higher power density due to the smaller total energy absorbed by the plasma.\u0000The increased repetition rate and an implemented self-referencing scheme still\u0000allowed for high-resolution, synchrotron-like NEXAFS measurements of Si3N4 and\u0000TiO2 thin films with 2.5 minute acquisition times. It was observed that\u0000degradation of the gas jet nozzle led to long-term instability of the source,\u0000which can be remediated using alternative nozzle designs. This work\u0000demonstrates the feasibility of achieving higher temporal resolution in future\u0000time-resolved X-ray absorption measurements using table-top laser-produced\u0000plasma sources","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Strain Optimization for ReBCO High-Temperature Superconducting Stellarator Coils in SIMSOPT SIMSOPT 中 ReBCO 高温超导恒星器线圈的应变优化

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.01925

Paul Huslage, Elisabeth J. Paul, Mohammed Haque. Pedro F. Gil, Nicolo Foppiani, Jason Smoniewsk, Eve. V. Stenson

{"title":"Strain Optimization for ReBCO High-Temperature Superconducting Stellarator Coils in SIMSOPT","authors":"Paul Huslage, Elisabeth J. Paul, Mohammed Haque. Pedro F. Gil, Nicolo Foppiani, Jason Smoniewsk, Eve. V. Stenson","doi":"arxiv-2409.01925","DOIUrl":"https://doi.org/arxiv-2409.01925","url":null,"abstract":"This work provides an optimization mechanism to ensure the compatibility of\u0000ReBCO (Rare-earth Barium Copper Oxide) high-temperature superconducting (HTS)\u0000tapes with non-planar stellarator coils. ReBCO coils enable higher field\u0000strengths and operating temperatures for the magnet systems of future fusion\u0000reactors but are sensitive to strain due to their brittle, ceramic functional\u0000layer. We have implemented a metric to optimize strain on stellarator coils\u0000made from ReBCO superconductors into the stellarator optimization framework\u0000texttt{SIMSOPT} and used it to design new stellarator coil configurations. To\u0000ensure structural integrity of coils wound with HTS tape, we introduce a\u0000penalty on binormal curvature and torsion along a coil. It can be used to\u0000optimize the orientation of the winding path for a given coil filament or to\u0000jointly optimize orientation and coil filament. We apply the strain\u0000optimization to three cases. For the EPOS (Electrons and Positrons in an\u0000Optimized Stellarator) design, we combine the strain penalty with an objective\u0000for quasisymmetry into a single-stage optimization; this enables us to find a\u0000configuration with excellent quasisymmetry at the smallest possible size\u0000compatible with the use of ReBCO tape. For CSX (Columbia Stellarator\u0000eXperiment), in addition to HTS strain, we add a penalty to prevent net tape\u0000rotation to ease the coil winding process. If the strain is calculated for a\u0000coil at reactor scale, we find a considerable variation of the binormal and\u0000torsional strain over the cross section of the large winding pack (0.5,m x\u00000.5,m). By exploiting the overall orientation of the winding pack as a degree\u0000of freedom, we can reduce binormal and torsional strains below limits for every\u0000ReBCO stack.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Single-pulse Gy-scale irradiation of biological cells at average dose-rates above $10^{13}$ Gy/s from a laser-wakefield accelerator 激光辐照加速器以高于 10^{13}$ Gy/s 的平均剂量率对生物细胞进行单脉冲 Gy 级辐照

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.01717

C. A. McAnespie, P. Chaudhary, M. J. V. Streeter, S. W. Botchway, N. Bourgeois, L. Calvin, N. Cavanagh, K. Fleck, D. Jaroszynski, B. Kettle, A. M. Lupu, S. P. D. Mangles, S. J. McMahon, J. Mill, S. R. Needham, P. P. Rajeev, K. M. Prise, G. Sarri

{"title":"Single-pulse Gy-scale irradiation of biological cells at average dose-rates above $10^{13}$ Gy/s from a laser-wakefield accelerator","authors":"C. A. McAnespie, P. Chaudhary, M. J. V. Streeter, S. W. Botchway, N. Bourgeois, L. Calvin, N. Cavanagh, K. Fleck, D. Jaroszynski, B. Kettle, A. M. Lupu, S. P. D. Mangles, S. J. McMahon, J. Mill, S. R. Needham, P. P. Rajeev, K. M. Prise, G. Sarri","doi":"arxiv-2409.01717","DOIUrl":"https://doi.org/arxiv-2409.01717","url":null,"abstract":"We report on the first experimental characterization of a laser-wakefield\u0000accelerator able to deliver, in a single pulse, doses in excess of 1 Gy on\u0000timescales of the order of tens of femtoseconds, reaching unprecedented average\u0000dose-rates above $10^{13}$ Gy/s. The irradiator is demonstrated to deliver\u0000doses tuneable up to 2.2 Gy in a cm$^2$ area and with a high degree of\u0000longitudinal and transverse uniformity in a single irradiation. In this regime,\u0000proof-of-principle irradiation of patient-derived glioblastoma stem-like cells\u0000and human skin fibroblast cells show indications of a differential cellular\u0000response, when compared to reference irradiations at conventional dose-rates.\u0000These include a statistically significant increase in relative biological\u0000effectiveness ($1.40pm0.08$ at 50% survival for both cell lines) and a\u0000significant reduction of the relative radioresistance of tumour cells. Data\u0000analysis provides preliminary indications that these effects might not be fully\u0000explained by induced oxygen depletion in the cells but may be instead linked to\u0000a higher complexity of the damages triggered by the ultra-high density of\u0000ionising tracks of femtosecond-scale radiation pulses. These results\u0000demonstrate an integrated platform for systematic radiobiological studies at\u0000unprecedented beam durations and dose-rates, a unique infrastructure for\u0000translational research in radiobiology at the femtosecond scale.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multiscale simulation of rarefied gas flows in Divertor Tokamak Test facility 多尺度模拟憩室托卡马克试验设备中的稀薄气体流

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-03 DOI: arxiv-2409.05895

Wei Li, Yanbing Zhang, Jianan Zeng, Lei Wu

引用次数: 0