arXiv - PHYS - Plasma Physics最新文献_第3页

On turbulent magnetic reconnection: fast and slow mean steady-states 关于湍流磁重联：快慢平均稳态

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-11 DOI: arxiv-2409.07346

Sage Stanish, David MacTaggart

引用次数: 0

Numerical Investigations on Dilute Cold Plasma Potential and Electron Temperature 稀冷等离子体电位和电子温度的数值研究

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06758

Shiying Cai, Chunpei Cai, Zhen Zhang

{"title":"Numerical Investigations on Dilute Cold Plasma Potential and Electron Temperature","authors":"Shiying Cai, Chunpei Cai, Zhen Zhang","doi":"arxiv-2409.06758","DOIUrl":"https://doi.org/arxiv-2409.06758","url":null,"abstract":"Simulation results are presented to demonstrate electron temperature and\u0000electrical potential development in dilute and cold plasma development. The\u0000simulation method is a hybrid method which adopted fluid model for electrons\u0000due to their high mobility, while heavy ions and neutrals are modelled with the\u0000direct simulation Monte Carlo and Particle-In-Cell methods. The flows include\u0000steady, starting-up and shutting-down scenarios. The goal is to illustrate the\u0000exponential behaviors which were predicted in several recently developed\u0000formulas. Those formulas include many coefficients related with local\u0000properties, and they are difficult to determine. Hence, those trends can only\u0000efficiently demonstrate by numerical simulations which are more convenient than\u0000experimental measurements. The results confirm several facts. For steady plasma\u0000flows, the electron temperature and potential profiles are smooth, very likely,\u0000they can be approximated with exponential functions. For unsteady flows, the\u0000property developing trends in the shutting down or starting-up processes change\u0000monotonically. Further, at locations with large gradients, the property change\u0000trends are less ideal than those formulas. This is consistent with the\u0000assumptions with which those formulas were developed.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196024","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

Theoretical Study of Inhomogeneity Effects on Three-Wave Parametric Instability: A WKBJ Approach 非均质性对三波参量不稳定性影响的理论研究：WKBJ 方法

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06677

Taotao Zhou, Nong Xiang, Chunyun Gan, Tianyang Xia

{"title":"Theoretical Study of Inhomogeneity Effects on Three-Wave Parametric Instability: A WKBJ Approach","authors":"Taotao Zhou, Nong Xiang, Chunyun Gan, Tianyang Xia","doi":"arxiv-2409.06677","DOIUrl":"https://doi.org/arxiv-2409.06677","url":null,"abstract":"The mechanisms by which media inhomogeneity affects the three wave parametric\u0000instability (PI), including the wave number mismatch and the parameter\u0000gradients, are investigated using an approach based on the\u0000Wentzel-Kramers-Brillouin-Jeffreys (WKBJ) approximation. This approach\u0000transforms the coupling wave equations into an amplitude equation and\u0000iteratively solves its characteristic polynomials. By analyzing the solutions,\u0000we proposed that the wave number of the quasi-mode, a key term in the wave\u0000number mismatch of non-resonant type PI, should be a complex root of the\u0000quasi-mode's linear dispersion equation. Based on this, we derive a unified\u0000amplification factor formula that covers the resonant and non-resonant, the\u0000forward-scattered and backward-scattered types of PI. The impact of parameter\u0000gradients on the local spatial growth rate becomes significant when the\u0000inhomogeneity exceeds 10^{-3}. Considering parameter gradients extends our\u0000approach's validity to an inhomogeneity of about 10^{-2}. This approach holds\u0000promise for more specific PI modeling in the future.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196027","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

Perfectly Matched Layer implementation for E-H fields and Complex Wave Envelope propagation in the Smilei PIC code Smilei PIC 代码中 E-H 场和复杂波包络传播的完美匹配层实现方法

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06287

Guillaume Bouchard, Arnaud Beck, Francesco Massimo, Arnd Specka

{"title":"Perfectly Matched Layer implementation for E-H fields and Complex Wave Envelope propagation in the Smilei PIC code","authors":"Guillaume Bouchard, Arnaud Beck, Francesco Massimo, Arnd Specka","doi":"arxiv-2409.06287","DOIUrl":"https://doi.org/arxiv-2409.06287","url":null,"abstract":"The design of absorbing boundary conditions (ABC) in a numerical simulation\u0000is a challenging task. In the best cases, spurious reflections remain for some\u0000angles of incidence or at certain wave lengths. In the worst, ABC are not even\u0000possible for the set of equations and/or numerical schemes used in the\u0000simulation and reflections can not be avoided at all. Perflectly Matched Layer\u0000(PML) are layers of absorbing medium which can be added at the simulation edges\u0000in order to significantly damp both outgoing and reflected waves, thus\u0000effectively playing the role of an ABC. They are able to absorb waves and\u0000prevent reflections for all angles and frequencies at a modest computational\u0000cost. It increases the simulation accuracy and negates the need of oversizing\u0000the simulation usually imposed by ABC and leading to a waste of computational\u0000resources and power. PML for finite-difference time-domain (FDTD) schemes in\u0000Particle-In-cell (PIC) codes are presented for both Maxwell's equations and,\u0000for the first time, the envelope wave equation. Being of the second order, the\u0000latter requires significant evolutions with respect to the former. It applies\u0000in particular to simulations of lasers propagating in plasmas using the reduced\u0000Complex Envelope model. The implementation is done in the open source code\u0000Smilei for both Cartesian and azimuthal modes (AM) decomposition geometries.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225105","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

Kink instability of flux ropes in partially-ionised plasmas 部分电离等离子体中通量绳的扭结不稳定性

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-10 DOI: arxiv-2409.06901

Giulia Murtas, Andrew Hillier, Ben Snow

{"title":"Kink instability of flux ropes in partially-ionised plasmas","authors":"Giulia Murtas, Andrew Hillier, Ben Snow","doi":"arxiv-2409.06901","DOIUrl":"https://doi.org/arxiv-2409.06901","url":null,"abstract":"In the solar atmosphere, flux ropes are subject to current driven\u0000instabilities that are crucial in driving plasma eruptions, ejections and\u0000heating. A typical ideal magnetohydrodynamics (MHD) instability developing in\u0000flux ropes is the helical kink, which twists the flux rope axis. The growth of\u0000this instability can trigger magnetic reconnection, which can explain the\u0000formation of chromospheric jets and spicules, but its development has never\u0000been investigated in a partially-ionised plasma (PIP). Here we study the kink\u0000instability in PIP to understand how it develops in the solar chromosphere,\u0000where it is affected by charge-neutral interactions. Partial ionisation speeds\u0000up the onset of the non-linear phase of the instability, as the plasma $beta$\u0000of the isolated plasma is smaller than the total plasma $beta$ of the bulk.\u0000The distribution of the released magnetic energy changes in fully and\u0000partially-ionised plasmas, with a larger increase of internal energy associated\u0000to the PIP cases. The temperature in PIP increases faster also due to heating\u0000terms from the two-fluid dynamics. PIP effects trigger the kink instability on\u0000shorter time scales, which is reflected in a more explosive chromospheric flux\u0000rope dynamics. These results are crucial to understand the dynamics of\u0000small-scale chromospheric structures - mini-filament eruptions - that this far\u0000have been largely neglected but could significantly contribute to chromospheric\u0000heating and jet formation.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"179 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196025","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

Enhancement of fusion reactivities using non-Maxwellian energy distributions 利用非麦克斯韦能量分布提高聚变反应活度

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-09 DOI: arxiv-2409.05848

Ben I. Squarer, Carlo Presilla, Roberto Onofrio

引用次数: 0

Integrating Novel Stellarator Single-Stage Optimization Algorithms to Design the Columbia Stellarator Experiment 整合新型恒星仪单级优化算法，设计哥伦比亚恒星仪实验

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-09 DOI: arxiv-2409.05261

A. Baillod, E. J. Paul, G. Rawlinson, M. Haque, S. W. Freiberger, S. Thapa

{"title":"Integrating Novel Stellarator Single-Stage Optimization Algorithms to Design the Columbia Stellarator Experiment","authors":"A. Baillod, E. J. Paul, G. Rawlinson, M. Haque, S. W. Freiberger, S. Thapa","doi":"arxiv-2409.05261","DOIUrl":"https://doi.org/arxiv-2409.05261","url":null,"abstract":"The Columbia Stellarator eXperiment (CSX), currently being designed at\u0000Columbia University, aims to test theoretical predictions related to QA plasma\u0000behavior, and to pioneer the construction of an optimized stellarator using\u0000three-dimensional, non-insulated high-temperature superconducting (NI-HTS)\u0000coils. The magnetic configuration is generated by a combination of two circular\u0000planar poloidal field (PF) coils and two 3D-shaped interlinked (IL) coils, with\u0000the possibility to add windowpane coils to enhance shaping and experimental\u0000flexibility. The PF coils and vacuum vessel are repurposed from the former\u0000Columbia Non-Neutral Torus (CNT) experiment, while the IL coils will be\u0000custom-wound in-house using NI-HTS tapes. To obtain a plasma shape that meets\u0000the physics objectives with a limited number of coils, novel single-stage\u0000optimization techniques are employed, optimizing both the plasma and coils\u0000concurrently, in particular targeting a tight aspect ratio QA plasma and\u0000minimized strain on the HTS tape. Despite the increased complexity due to the\u0000expanded degrees of freedom, these methods successfully identify optimized\u0000plasma geometries that can be realized by coils meeting engineering\u0000specifications. This paper discusses the derivation of the constraints and\u0000objectives specific to CSX, and describe how two recently developed\u0000single-stage optimization methodologies are applied to the design of CSX. A set\u0000of selected configurations for CSX is then described in detail.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142196030","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

Rapid, strongly magnetized accretion in the zero-net-vertical-flux shearing box 零网垂直流剪切箱中的快速强磁化增生

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-09 DOI: arxiv-2409.05467

Jonathan Squire, Eliot Quataert, Philip F. Hopkins

{"title":"Rapid, strongly magnetized accretion in the zero-net-vertical-flux shearing box","authors":"Jonathan Squire, Eliot Quataert, Philip F. Hopkins","doi":"arxiv-2409.05467","DOIUrl":"https://doi.org/arxiv-2409.05467","url":null,"abstract":"We show that there exist two qualitatively different turbulent states of the\u0000zero-net-vertical-flux shearing box. The first, which has been studied in\u0000detail previously, is characterized by a weakly magnetized ($betasim50$)\u0000midplane with slow periodic reversals of the mean azimuthal field (dynamo\u0000cycles). The second (the \"low-$beta$ state\"), which is the main subject of\u0000this paper, is characterized by a strongly magnetized $betasim1$ midplane\u0000dominated by a coherent azimuthal field with much stronger turbulence and much\u0000larger accretion stress $alpha sim 1$. The low-$beta$ state is realized in\u0000simulations that begin with sufficiently strong azimuthal magnetic fields. The\u0000mean azimuthal field in the low-$beta$ state is quasi steady (no cycles) and\u0000is sustained by a dynamo mechanism that compensates for the continued loss of\u0000magnetic flux through the vertical boundaries; we attribute the dynamo to the\u0000combination of differential rotation and the Parker instability, although many\u0000of its details remain unclear. Vertical force balance in the low-$beta$ state\u0000is dominated by the mean magnetic pressure except at the midplane, where\u0000thermal pressure support is always important (this is true even when\u0000simulations are initialized at $betall1$, provided the thermal scale-height\u0000of the disk is well-resolved). The efficient angular momentum transport in the\u0000low-$beta$ state may resolve long-standing tension between predictions of\u0000magnetorotational turbulence (at high $beta$) and observations; likewise, the\u0000bifurcation in accretion states we find may be important for understanding the\u0000state transitions observed in dwarf novae, X-ray binaries, and changing-look\u0000AGN. We discuss directions for future work including the implications of our\u0000results for global accretion disk simulations.","PeriodicalId":501274,"journal":{"name":"arXiv - PHYS - Plasma Physics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225086","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

Faraday shield dissipation in the drivers of SPIDER based on electromagnetic 3D calculations 基于电磁 3D 计算的 SPIDER 驱动器中的法拉第屏蔽损耗

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-09 DOI: arxiv-2409.05821

D. López-Bruna, S. Denizeau, I. Predebon, A. La Rosa, C. Poggi, P. Agostinetti

引用次数: 0

Wideband Glide-Symmetric Double-Corrugated Gap-Waveguide Traveling-Wave Tube for Millimeter Waves 用于毫米波的宽带滑动对称双波纹间隙波导行波管

arXiv - PHYS - Plasma Physics Pub Date : 2024-09-08 DOI: arxiv-2409.05238

Miguel Saavedra-Melo, Nelson Castro, Robert Marosi, Eva Rajo-Iglesias, Filippo Capolino

引用次数: 0