Physics of Plasmas最新文献_第3页

Measurement of early time outer laser beam reflection inside a cylindrical hohlraum at the National Ignition Facility 在国家点火装置的圆柱形炉膛内测量早期时间外激光束反射

Physics of Plasmas Pub Date : 2024-06-01 DOI: 10.1063/5.0201962

Hui Chen, D. T. Woods, N. Lemos, M. Rosen, O. Landen, J. Milovich, M. B. Schneider, C. Trosseille, J. Delora-Ellefson, M. Hardy, N. Hash, D. Hinkel, J. Holder, N. Izumi, N. Masters, W. Montgomery, J. D. Moody, K. Newman, S. Rogers, J. S. Ross, V. Smalyuk, C. Weber, T. Zobrist

{"title":"Measurement of early time outer laser beam reflection inside a cylindrical hohlraum at the National Ignition Facility","authors":"Hui Chen, D. T. Woods, N. Lemos, M. Rosen, O. Landen, J. Milovich, M. B. Schneider, C. Trosseille, J. Delora-Ellefson, M. Hardy, N. Hash, D. Hinkel, J. Holder, N. Izumi, N. Masters, W. Montgomery, J. D. Moody, K. Newman, S. Rogers, J. S. Ross, V. Smalyuk, C. Weber, T. Zobrist","doi":"10.1063/5.0201962","DOIUrl":"https://doi.org/10.1063/5.0201962","url":null,"abstract":"In a National Ignition Facility (NIF) cylindrical hohlraum, any specular reflection (“glint”) off the wall from the outer cone (incident angle of 50° and 44° relative to the surface of the wall) laser beam will irradiate the capsule poles. If the glint power is sufficiently large during the picket (early time) of the laser pulse, it may seed high-mode perturbations on the capsule surface that can grow during the implosion. To quantify the glint power on the capsule during the picket by the outer beams, we performed dedicated experiments on NIF using a flat witness foil as a surrogate for the capsule in a half-hohlraum target. We found that the measured glint power is approximately comparable to simulations using a nominal electron conduction flux limiter of f = 0.15, and over an order of magnitude lower than that predicted using f = 0.03 in the wall. Based on our current understanding, we conclude that the glint from the outer beams plays an insignificant role in capsule drive asymmetry.","PeriodicalId":510396,"journal":{"name":"Physics of Plasmas","volume":"57 49","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141275022","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

Coupled relativistic magnetrons with phase-locked Gaussian radiation pattern 具有锁相高斯辐射模式的耦合相对论磁控管

Physics of Plasmas Pub Date : 2024-06-01 DOI: 10.1063/5.0206029

Sha Xu, L. Lei, Ziyun Yao, Yong Zhang, F. Qin, Yue Cui, Zhi-kai Fan, Dong Wang

引用次数: 0

Simulating energetic ions and enhanced fusion rates from ion-cyclotron resonance heating with a full-wave/Fokker–Planck model 用全波/福克-普朗克模型模拟高能离子和离子-回旋共振加热产生的增强聚变率

Physics of Plasmas Pub Date : 2024-06-01 DOI: 10.1063/5.0204671

S. Frank, J. C. Wright, P. Rodriguez-Fernandez, N. T. Howard, P. Bonoli

{"title":"Simulating energetic ions and enhanced fusion rates from ion-cyclotron resonance heating with a full-wave/Fokker–Planck model","authors":"S. Frank, J. C. Wright, P. Rodriguez-Fernandez, N. T. Howard, P. Bonoli","doi":"10.1063/5.0204671","DOIUrl":"https://doi.org/10.1063/5.0204671","url":null,"abstract":"Reproducing fast-ion enhanced fusion rates from ion-cyclotron resonance heating (ICRH) in tokamaks requires the self-consistent coupling of a full-wave solver and a Fokker–Planck solver, which evolves multiple simultaneously resonant ion species. We introduce a new self-consistent model that iterates the TORIC full-wave solver with the CQL3D Fokker–Planck solver using the integrated plasma simulator (IPS). This model evolves the bounce-averaged ion distribution functions in both parallel and perpendicular velocity-space with a quasilinear radio frequency (RF) diffusion operator valid in the ion finite Larmor radius (FLR) limit and the RF electric fields with the resultant non-Maxwellian FLR dielectric tensor. This produces non-Maxwellian ICRH simulations that are fully self-consistent, fast, and interoperable with integrated modeling frameworks, such as TRANSP/GACODE/IPS-FASTRAN. We demonstrate our model's capabilities by validating it against experimental data in Alcator C-Mod. We then perform the first RF heating simulations of SPARC using self-consistent non-Maxwellian ion distributions to investigate the potential to enhance fusion rates using ion cyclotron resonance heating generated fast ions.","PeriodicalId":510396,"journal":{"name":"Physics of Plasmas","volume":"12 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141274521","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

Void closure in a pulsed complex plasma in microgravity 微重力脉冲复合等离子体中的空隙闭合

Physics of Plasmas Pub Date : 2024-06-01 DOI: 10.1063/5.0204998

C. Knapek, D. Mohr, P. Huber

{"title":"Void closure in a pulsed complex plasma in microgravity","authors":"C. Knapek, D. Mohr, P. Huber","doi":"10.1063/5.0204998","DOIUrl":"https://doi.org/10.1063/5.0204998","url":null,"abstract":"A new experimental method for creating void-free complex (dusty) plasmas under microgravity conditions is presented. The method is based on a pulsed operation mode of a four-channel radio frequency generator for plasma sustainment. A dust cloud of micrometer-sized particles can be immersed in the bulk of a low temperature plasma under microgravity conditions. It typically contains a central volume depleted of particles—the void—that prevents the generation of large, continuous clouds. Experiments performed at different neutral gas pressures and discharge volumes during the microgravity phase of a parabolic flight show that the central void is closed completely once the pulsed operation mode is applied. The particle cloud shape and the density distribution within the cloud are practically independent of the pulse period within the investigated parameter range and mainly depend on the overall discharge parameters neutral gas pressure and discharge volume. This indicates that the pulsed operation of the plasma source does not introduce new physical effects on the particles aside from the void closure. The proposed method has great potential for future application in experimental facilities dedicated to fundamental studies of large three-dimensional, homogeneous complex plasma systems in microgravity.","PeriodicalId":510396,"journal":{"name":"Physics of Plasmas","volume":"56 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141275711","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

Twisted terahertz excitation using pre-bunched relativistic electron beam in magnetic wiggler 利用磁摇摆器中的预束相对电子束进行扭曲太赫兹激励

Physics of Plasmas Pub Date : 2024-06-01 DOI: 10.1063/5.0206098

Himani Juneja, A. Panwar, Prashant Chauhan

引用次数: 0

Synergistic enhancement of laser-proton acceleration with integrated targets 利用集成靶协同增强激光-质子加速

Physics of Plasmas Pub Date : 2024-05-01 DOI: 10.1063/5.0195634

Zhipeng Liu, Ying Gao, Qingfan Wu, Z. Pan, Yulan Liang, Tan Song, Tianqi Xu, Y. Shou, Yujia Zhang, Haoran Chen, Qihang Han, Chenghao Hua, Xun Chen, Shirui Xu, Z. Mei, Pengjie Wang, Z.-K. Peng, Jiarui Zhao, Shiyou Chen, Yanying Zhao, Xueqing Yan, Wenjun Ma

{"title":"Synergistic enhancement of laser-proton acceleration with integrated targets","authors":"Zhipeng Liu, Ying Gao, Qingfan Wu, Z. Pan, Yulan Liang, Tan Song, Tianqi Xu, Y. Shou, Yujia Zhang, Haoran Chen, Qihang Han, Chenghao Hua, Xun Chen, Shirui Xu, Z. Mei, Pengjie Wang, Z.-K. Peng, Jiarui Zhao, Shiyou Chen, Yanying Zhao, Xueqing Yan, Wenjun Ma","doi":"10.1063/5.0195634","DOIUrl":"https://doi.org/10.1063/5.0195634","url":null,"abstract":"In proton acceleration from laser-irradiated thin foil targets, adding foams on the front surface or connecting a helical coil on the rear surface of the foil has proven to be an effective scheme to enhance proton energy. In this paper, we make the first attempt to incorporate the above two enhancement schemes for laser-proton acceleration by simultaneously adding foams and connecting a helical coil to a thin foil target. By utilizing such integrated targets in the experiment, focused beams were generated. The maximum proton energy and the number of energetic protons are apparently enhanced. Moreover, quasi-monoenergetic peaks were formed at the high-energy end of the spectra. Particle-in-cell plasma simulations and electromagnetic beam dynamics simulations show that the double-layer target not only enhances the energy of protons but also leads to a multiple-fold increase in the number of escaped electrons, which results in an enhanced post-acceleration in helical coil subsequently.","PeriodicalId":510396,"journal":{"name":"Physics of Plasmas","volume":"26 38","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141137299","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

Expulsion of hydrogen negative ions by the anode layer of negative space charge from Penning discharge with metal hydride cathodes 带金属氢化物阴极的潘宁放电负空间电荷阳极层释放氢负离子

Physics of Plasmas Pub Date : 2024-05-01 DOI: 10.1063/5.0202579

I. Sereda, Y. Hrechko, M. Azarenkov

引用次数: 0

Edge modes of the Helmholtz–Onsager gas in a multiply connected domain 多连通域中的亥姆霍兹-昂萨格气体边缘模式

Physics of Plasmas Pub Date : 2024-05-01 DOI: 10.1063/5.0193438

Richard McQueen, Chjan C. Lim

引用次数: 0

Investigation of triangularity impact on impurity content in JET-ILW H, D, T, and DT plasmas 研究三角形对 JET-ILW H、D、T 和 DT 等离子体中杂质含量的影响

Physics of Plasmas Pub Date : 2024-05-01 DOI: 10.1063/5.0207343

W. Gromelski, C. Angioni, A. Chomiczewska, D. Fajardo, I. Ivanova-Stanik, Damian King, E. Kowalska-Strzęciwilk, M. Maslov, E. Pawelec, P. Schneider

{"title":"Investigation of triangularity impact on impurity content in JET-ILW H, D, T, and DT plasmas","authors":"W. Gromelski, C. Angioni, A. Chomiczewska, D. Fajardo, I. Ivanova-Stanik, Damian King, E. Kowalska-Strzęciwilk, M. Maslov, E. Pawelec, P. Schneider","doi":"10.1063/5.0207343","DOIUrl":"https://doi.org/10.1063/5.0207343","url":null,"abstract":"The work presents the recent outcome of the research on Joint European Torus with ITER-like wall (JET-ILW) concerning Be, mid-Z (Ni, Cu, Fe), and high-Z (W) impurities for a selection of Neutral Beam Injection-heated, ELMy H-mode pulses using visible and vacuum–ultraviolet spectroscopy together with bolometry diagnostic. The investigation is focused on the evaluation of the plasma triangularity (δ) impact on the impurity radiation in hydrogen (H), deuterium (D), tritium (T), and deuterium–tritium (DT) plasmas for pulses described in [P. A. Schneider, Nucl. Fusion 63, 112010 (2023)]. The variations of δ were in the range of 0.21–0.31 for different time windows with low magnetic toroidal field (Bt=1.7 T) and plasma current (Ip=1.4 MA) in the corner–corner configuration, that is with both the inner and outer strike points on the horizontal W-coated divertor target plates. The results confirm the rise in Be flux with plasma isotope and lower δ leading to higher plasma density close to the plasma wall. The dominant role of W as a source of plasma radiation has also been confirmed. For mid-Z impurities and W, the variations in their densities due to δ change are negligible and the rise in their densities is observed with higher isotope mass, although this effect is often masked by the dominant role of ELM frequency on the impurity level. The impurity radiation losses based on bolometry together with the W intensity are ruled by the changes in the electron density and are well correlated when the Te profiles are conserved.","PeriodicalId":510396,"journal":{"name":"Physics of Plasmas","volume":"154 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141133674","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

Propagation of twisted laser carrying orbital angular momentum in magnetized plasma 携带轨道角动量的扭曲激光在磁化等离子体中的传播

Physics of Plasmas Pub Date : 2024-05-01 DOI: 10.1063/5.0206828

Subhajit Bhaskar, Hitendra K. Malik

{"title":"Propagation of twisted laser carrying orbital angular momentum in magnetized plasma","authors":"Subhajit Bhaskar, Hitendra K. Malik","doi":"10.1063/5.0206828","DOIUrl":"https://doi.org/10.1063/5.0206828","url":null,"abstract":"The propagation of electromagnetic beams carrying orbital angular momentum l is investigated in a cold collisionless plasma where a static magnetic field is applied in the axial direction. The relativistic and ponderomotive nonlinearities are taken into consideration simultaneously. A stationary nonlinear Schrödinger equation is derived using the Wentzel–Kramers–Brillouin method and the slowly varying envelope approximation. The critical condition for the self-trapped mode is achieved as a function of orbital angular momentum (OAM), magnetic field, and initial laser intensity of the beam. The response of the medium to the two types of polarizations, i.e., left circular polarization (LCP) and right circular polarization (RCP), is compared, and it is observed that the RCP laser shows better focusing than the LCP laser and also requires a smaller beam radius for achieving the self-trapped mode. The effect of applied magnetic field and OAM of the laser is also studied on the beam width evolution. The laser is found to be focused earlier in the cases of a larger applied magnetic field. A Laguerre–Gaussian laser with higher OAM is observed to show efficient self-focusing. This study enables exploration in the fields of particle acceleration, electron bunch generation, x-ray sources, and more.","PeriodicalId":510396,"journal":{"name":"Physics of Plasmas","volume":"98 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141135665","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