2022 IEEE International Conference on Plasma Science (ICOPS)最新文献_第8页

Exploring Cesium and H-Beam Properties Internal to the Lansce H-Ion Source Using Resonant Absorption Spectroscopy and Cavity Ring Down Spectroscopy 用共振吸收光谱和腔衰荡光谱研究兰斯h离子源内部铯和h束的性质

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/ICOPS45751.2022.9813046

D. Kleinjan, G. Rouelau, L. Neukirch

引用次数: 0

Helicon Core Formation: A Global Transport Bifurcation Leading to a Radial Transport Barrier and Spontaneous Axial Plasma Detachment 螺旋核的形成:导致径向输运屏障和自发轴向等离子体分离的全球输运分岔

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/icops45751.2022.9813210

S. C. Thakur

{"title":"Helicon Core Formation: A Global Transport Bifurcation Leading to a Radial Transport Barrier and Spontaneous Axial Plasma Detachment","authors":"S. C. Thakur","doi":"10.1109/icops45751.2022.9813210","DOIUrl":"https://doi.org/10.1109/icops45751.2022.9813210","url":null,"abstract":"We report that helicon core formation in rf devices is accompanied by the formation of a radial transport barrier and simultaneous axial plasma detachment; via a self-organized global transition due to a transport bifurcation [1] . Evidence from both Langmuir probes and fast imaging show that the radial extent of the transport barrier is similar to the width of the helicon core. Using spectroscopy and neutral pressure measurements, we simultaneously observe axial plasma detachment, which follow the same hysteresis patterns associated with the radial transport bifurcation. We report dramatic changes in both mean and fluctuation profiles across this transition. This spontaneous self-organized global transition is universal, but the transition-threshold depends on the helicon source parameters. 2-D bifurcation diagrams elucidate various regimes of operation of rf plasma sources (Capacitively Coupled Plasmas, Inductively Coupled Plasmas, Helicon-detached, helicon-attached), allowing access to study basic plasma instabilities, turbulence and transport, as well as divertor-relevant plasma detachment in the same device. Spontaneous plasma detachment has serious implications on the relevance of similar rf devices [2] , [3] designed to study Plasma Material Interactions (PMI). In addition, this also gives us the opportunity to study instabilities, turbulence and transport associated with detached plasmas [4] , [5] .","PeriodicalId":175964,"journal":{"name":"2022 IEEE International Conference on Plasma Science (ICOPS)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117171785","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

First Divertor Thomson Scattering Measurements on Mast-U 桅杆- u上第一分流器汤姆逊散射测量

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/ICOPS45751.2022.9813181

J. Clark, M. Bowden, Y. Kim, B. Parry, E. Rose, R. Sarwar, R. Scannell

引用次数: 0

Energy Confinement Time in a Magnetically Confined Thermonuclear Fusion Reactor 磁约束热核聚变反应堆的能量约束时间

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/ICOPS45751.2022.9813043

C. Chen, J. Becker, J. J. Farrell

引用次数: 0

New Laser-Induced Fluorescence-Dip Spectroscopy for Weak Electric Field Measurements in Plasma 用于等离子体弱电场测量的新型激光诱导荧光dip光谱

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/icops45751.2022.9813005

W. An, G. Mueller, A. Weisenburger, Z. Wang

{"title":"New Laser-Induced Fluorescence-Dip Spectroscopy for Weak Electric Field Measurements in Plasma","authors":"W. An, G. Mueller, A. Weisenburger, Z. Wang","doi":"10.1109/icops45751.2022.9813005","DOIUrl":"https://doi.org/10.1109/icops45751.2022.9813005","url":null,"abstract":"In laser-induced fluorescence-dip spectroscopy the resonance range of the Stark-shift is probed by tuning the excitation laser when measuring the absorption spectra [1] . Thus, in order to work out a single measuring point a very reproducible field distribution in the plasma over time or from pulse to pulse is required. The new method enables the measurement range to be extended to plasmas in pulsed systems with frequently poor microscale pulse-to-pulse reproducibility. The core element of the diagnostics is a special broadband dye laser for the excitation of Rydberg levels in xenon. With a bandwidth of 1 nm, it is possible to record a wide range of Stark shifts in just one measurement step. Depending on the applications, two variants of diagnostics can be used either independently or in addition: semi-quantitative determination of the one-dimensional electric field distribution stretched to the area of a few cm and spot measurement of the field strength with high spatial and spectral resolution. The proposed diagnostic enables the measurement of electric fields with high temporal (5 ns) and spatial (tens of μm) resolution with sensitivity of 200 V/cm and accuracy of 20 V/cm. However, this is not the limit of the diagnosis. The sensitivity can be lower than 100 V / cm if higher principal quantum numbers are chosen for the Rydberg levels (n> 20).","PeriodicalId":175964,"journal":{"name":"2022 IEEE International Conference on Plasma Science (ICOPS)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126060603","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

Power Flow Effects of the Applied Axial Magnetic Field on Maglif Experiments at the Z Machine 轴向外加磁场对Z机磁振实验的功率流效应

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/ICOPS45751.2022.9813052

D. Zimmer

{"title":"Power Flow Effects of the Applied Axial Magnetic Field on Maglif Experiments at the Z Machine","authors":"D. Zimmer","doi":"10.1109/ICOPS45751.2022.9813052","DOIUrl":"https://doi.org/10.1109/ICOPS45751.2022.9813052","url":null,"abstract":"The Z machine is a pulsed power generator capable of producing >20 MA current pulses and is used in a variety of HEDP experiments including x-ray production, materials science, and fusion energy [1] . A challenge, faced particularly by the Magnetized Liner Inertial Fusion (MagLIF) experiments, is that multi-MA current losses are routinely observed [2] . Current loss attributed to plasma formation in the double post-hole convolute has been a previous focus of inquiry [3] , though recent developments of velocimetry-based current diagnostics have enabled current measurements closer to the load [4] . This diagnostic capability enables the study of loss mechanisms interior to the convolute, where MagLIF’s applied axial magnetic field intersects with the final transmission line. Since the inner transmission lines on Z are insulated by the self-magnetic field generated from the current pulse, changes to the field topology could significantly increase shunted current. We explore the hypothesis that the applied axial magnetic field interferes with magnetic insulation and drives current to shunt prior to the experimental load. Analytical calculations, 2D fluid simulations, and experimental measurements will be presented.","PeriodicalId":175964,"journal":{"name":"2022 IEEE International Conference on Plasma Science (ICOPS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129970107","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

Electronic Stopping Power of Ions in Cold Targets and Warm Plasmas 离子在冷靶和热等离子体中的电子停止能力

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/icops45751.2022.9813258

M. Gu, T. Mehlhorn, I. Golovkin

{"title":"Electronic Stopping Power of Ions in Cold Targets and Warm Plasmas","authors":"M. Gu, T. Mehlhorn, I. Golovkin","doi":"10.1109/icops45751.2022.9813258","DOIUrl":"https://doi.org/10.1109/icops45751.2022.9813258","url":null,"abstract":"We report on a new wide range electronic stopping power model that builds on the random phase approximation (RPA) dielectric response formalism of Wang, et al [1] and the local density approximation (LDA) with electronic density distributions calculated in an average atom model using the Flexible Atomic Code (FAC) [2] . The accuracy of this model has been greatly improved by implementing several extensions to RPA theory including a strong collision correction based on the binary collision theory of Zwicknagel for k>kmax [3] , a static local field correction [4] , an electron binding energy correction, and the Barkas effect [5] . The combined corrections bring our RPA-LDA proton stopping power results in cold targets into close agreement with experiments across the periodic table (PSTAR database). We will also show results for the stopping of ions in warm dense plasmas as compared with the published data. We will describe our plans to implement this accurate ion stopping power model into an efficient and robust framework for computing ion energy deposition in HED plasmas spanning a wide range of temperatures and densities and to incorporate them into the HELIOS-CR hydro code (Prism) and Chicago (Voss), as well as an open source standalone code.","PeriodicalId":175964,"journal":{"name":"2022 IEEE International Conference on Plasma Science (ICOPS)","volume":"1999 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128260562","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: 1

Autofluorescence-Guided Removal of Bacterial Biofilms from Wound Surfaces Using Cold Atmospheric Pressure Plasma 利用冷常压等离子体自荧光引导去除伤口表面的细菌生物膜

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/ICOPS45751.2022.9812961

M. Okebiorun, C. Waite, S. Clark, C. Oberbeck, D. Miller, K. Cornell, J. Browning

{"title":"Autofluorescence-Guided Removal of Bacterial Biofilms from Wound Surfaces Using Cold Atmospheric Pressure Plasma","authors":"M. Okebiorun, C. Waite, S. Clark, C. Oberbeck, D. Miller, K. Cornell, J. Browning","doi":"10.1109/ICOPS45751.2022.9812961","DOIUrl":"https://doi.org/10.1109/ICOPS45751.2022.9812961","url":null,"abstract":"Cold atmospheric pressure plasma (CAP) has shown potential to completely remove biofilms from surfaces [1] , [2] . The goal of this study is to employ the autofluorescence nature of bacterial biofilms to guide the removal of these biofilms from wounds using a CAP scalpel. Pseudomonas fluorescens biofilms which produce a green fluorescence under 405 nm UV light were grown on 12 chicken samples. The wound model (chicken tissue) is placed on a motorized X-Y stage with the plasma discharge device directly facing the sample. An image of the fluorescent biofilm region is captured using a Mightex BCN-B013-U monochrome camera and 560 nm green filter. The captured image then guides the X-Y stage to move such that only the fluorescent region is treated with CAP. CAP treatment of biofilm regions was carried out using a 1.37 lpm Ar/H 2 O plasma device with 39.5 x 54 mm dimension and a 1.5 mm tip. The discharge voltage and current are 3.24 kV and 1.2 mA respectively. The average speed of the plasma discharge over the substrate is 1 mm/s and the gap between the substrate and the discharge is 2 mm. To evaluate the action of CAP on the sample, before and after-fluorescent images were compared, CFU counts were taken, and 3D view of the effects were observed using a confocal microscope.","PeriodicalId":175964,"journal":{"name":"2022 IEEE International Conference on Plasma Science (ICOPS)","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124601016","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

Low Velocity Proton Stopping Power Measurements in Warm Dense Carbon 热致密碳中低速质子停止功率的测量

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/icops45751.2022.9813238

S. Malko, W. Cayzac, V. Ospina-Bohórquez, K. Bhutwala, M. Bailly-Grandvaux, C. McGuffey, R. Fedosejevs, X. Vaisseau, A. Tauschwitz, J. I. Apiñaniz, D. De Luis, G. Gatti, M. Huault, J. A. Pérez-Hernández, S. Hu, A. White, L. Collins, K. Nichols, P. Neumayer, G. Faussurier, J. Vorberger, W. Fox, B. Frances Kraus, D. Schaeffer, G. Prestopino, C. Verona, J. Santos, D. Batani, F. Beg

引用次数: 0

Three-Species Plasma-Neutral Modeling of THz Breakdown for Passive Plasma-Based Photonic Crystal Devices 被动等离子体光子晶体器件太赫兹击穿的三种等离子体中性模型

2022 IEEE International Conference on Plasma Science (ICOPS) Pub Date : 2022-05-22 DOI: 10.1109/ICOPS45751.2022.9813176

W. Thomas, E. Meier, U. Shumlak

{"title":"Three-Species Plasma-Neutral Modeling of THz Breakdown for Passive Plasma-Based Photonic Crystal Devices","authors":"W. Thomas, E. Meier, U. Shumlak","doi":"10.1109/ICOPS45751.2022.9813176","DOIUrl":"https://doi.org/10.1109/ICOPS45751.2022.9813176","url":null,"abstract":"Plasma photonic crystals (PPCs) have the potential to significantly expand the capabilities of current millimeter wave filtering and switching technologies by providing high speed (μs) control of energy band-gap/pass characteristics in the GHz through low THz range. Furthermore, dielectric photonic crystals can be functionalized with self-initiated plasmas in resonant defects to provide passive power modulation. Constructing experimental devices in the low THz range is challenging, requiring plasma densities on the order of 10 22 m -3 , and sub-millimeter device characteristic lengths. Drift-diffusion models typically used in low temperature and process plasma simulations rely on reaction rate and transport coefficients calculated by Boltzmann solvers that assume low ionization fractions (<10 -5 ), and steady-state electric fields and electron densities. Ad hoc extensions to temporally and spatially varying fields must be made. Exploring computationally tractable alternative methods for high-density and high-ionization-fraction reacting plasma-neutral mixtures is therefore strongly motivated. In this work, an existing three-species (electron-ion-neutral atom) 5-moment model developed by Meier and Shumlak [ Physics of Plasmas , 19, 7, (2012)] is extended to include electron-neutral relative velocity in reaction rates in order to capture electrostatic and AC breakdown. Initial results and model validation for a THz argon plasma are presented.","PeriodicalId":175964,"journal":{"name":"2022 IEEE International Conference on Plasma Science (ICOPS)","volume":"07 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130161774","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