Observations of pressure anisotropy effects within semi-collisional magnetized plasma bubbles

AbstractMagnetized plasma interactions are ubiquitous in astrophysical and laboratory plasmas. Various physical effects have been shown to be important within colliding plasma flows influenced by opposing magnetic fields, however, experimental verification of the mechanisms within the interaction region has remained elusive. Here we discuss a laser-plasma experiment whereby experimental results verify that Biermann battery generated magnetic fields are advected by Nernst flows and anisotropic pressure effects dominate these flows in a reconnection region. These fields are mapped using time-resolved proton probing in multiple directions. Various experimental, modelling and analytical techniques demonstrate the importance of anisotropic pressure in semi-collisional, high-β plasmas, causing a reduction in the magnitude of the reconnecting fields when compared to resistive processes. Anisotropic pressure dynamics are crucial in collisionless plasmas, but are often neglected in collisional plasmas. We show pressure anisotropy to be essential in maintaining the interaction layer, redistributing magnetic fields even for semi-collisional, high energy density physics (HEDP) regimes.

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Synthesis, Characterization and Evaluation of Supercapacitive Response of Dodecylbenzenesulphonic Acid (DBSA) Doped Polypyrrole/Zirconium Dioxide Composites

Polymers ◽

10.3390/polym13224035 ◽

2021 ◽

Vol 13 (22) ◽

pp. 4035

Author(s):

Rizwan Ullah ◽

Mehtab Khan ◽

Rozina Khattak ◽

Nadia Khan ◽

Muhammad Sufaid Khan ◽

...

Keyword(s):

High Performance ◽

Specific Capacity ◽

Synthesis Method ◽

Analytical Techniques ◽

High Energy ◽

High Energy Density ◽

X Ray Diffraction ◽

Vis Spectroscopy ◽

Micro Morphology ◽

Synthesized Materials

An in-situ chemical oxidative method was used to effectively synthesize a promising supercapacitor material based on PPy/ZrO2 composites. The synthesized materials were characterized by different analytical techniques, such as UV/visible (UV/Vis) spectroscopy, Fourier-transform infra-red spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The inclusion of ZrO2 into the PPy matrix was verified by vibrational spectra and structural analyses. The (TGA) results showed that incorporating ZrO2 into the polymeric matrix improved its thermal stability. In addition, the electrochemical properties of the synthesizedmaterials were investigated byusing cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD). The PPy/ZrO2 composite demonstrated excellent super capacitive performance, and high specific capacity of 337.83 F/g, with an exceedingly high energy density of 187.68 Wh/kg at a power density of 1000 W/kg. The composite materials maintain good stability after 1000 charge and discharge cycles, with 85% capacitance retention. The PPy/ZrO2 possesses a high capacitance, an attractive micro-morphology, and a simple synthesis method. The findings indicate that the PPy/ZrO2 composite could be a promising electrode material for high-performance supercapacitor applications.

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Optical characteristics of finite temperature quantum electron gas

Canadian Journal of Physics ◽

10.1139/cjp-2017-0182 ◽

2017 ◽

Vol 95 (12) ◽

pp. 1225-1233

Author(s):

M. Akbari-Moghanjoughi

Keyword(s):

High Energy ◽

Magnetized Plasma ◽

High Energy Density ◽

Diffraction Effect ◽

Optical Parameters ◽

Characteristic Frequencies ◽

Quantum Equation ◽

Electron Fluid ◽

Quantum Diffraction ◽

Transverse Electromagnetic

In this paper we study the propagation of elliptically polarized transverse electromagnetic waves in a quasineutral plasma with arbitrary degenerate electron fluid ranging from classical dilute to fully degenerate density regimes by using the appropriate collisional magnetohydrodynamics model, which incorporates the adiabatic quantum equation of states for high-frequency electron fluid compression and the Bohm quantum potential responsible for the collective quantum diffraction effect. Three distinct propagation modes are categorized corresponding to electron density regimes of dilute, intermediate, and fully degenerate plasmas. One of these modes is found to be purely of quantum mechanical origin and disappears in the absence of the quantum diffraction effect. The present generalized magnetohydrodynamics theory qualitatively describes key features of optical parameters and experimental data of dilute classical, semiconducting, and in fully degenerate plasmas. Different optical parameters, such as the refractive and absorption index of the new mode are investigated. It is shown that the optical response of the magnetized plasma with arbitrary degeneracy is essentially governed by three characteristic frequencies, namely, collision, plasmon, and cyclotron frequencies. The profound experimental minimum in the refractive index of arbitrary degenerate quantum plasmas and its dependence on the characteristic frequencies is studied in detail. Current investigation is of fundamental importance in high energy density and fusion plasma diagnostics and may provide key knowledge on the characteristics of astrophysical dense matter.

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Seeding magnetic fields for laser-driven flux compression in high-energy-density plasmas

Review of Scientific Instruments ◽

10.1063/1.3115983 ◽

2009 ◽

Vol 80 (4) ◽

pp. 043504 ◽

Cited By ~ 40

Author(s):

O. V. Gotchev ◽

J. P. Knauer ◽

P. Y. Chang ◽

N. W. Jang ◽

M. J. Shoup ◽

...

Keyword(s):

Energy Density ◽

Magnetic Fields ◽

High Energy ◽

High Energy Density ◽

Flux Compression ◽

High Energy Density Plasmas

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Structural evolution of high energy density V3+/V4+ mixed valent Na3V2O2x(PO4)2F3−2x (x = 0.8) sodium vanadium fluorophosphate using in situ synchrotron X-ray powder diffraction

Journal of Materials Chemistry A ◽

10.1039/c4ta00773e ◽

2014 ◽

Vol 2 (21) ◽

pp. 7766-7779 ◽

Cited By ~ 43

Author(s):

Paula Serras ◽

Verónica Palomares ◽

Teófilo Rojo ◽

Helen E. A. Brand ◽

Neeraj Sharma

Keyword(s):

Structural Evolution ◽

High Energy ◽

High Energy Density ◽

Sodium Ion Battery ◽

Time Resolved ◽

X Ray ◽

Xrd Study ◽

First Time ◽

Synchrotron Xrd

The first time-resolved in situ synchrotron XRD study of a cathode in a functioning sodium-ion battery. We determine the reaction mechanism, lattice parameters, sodium evolution, and the maximum sodium extraction for the fresh and precycled cell.

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Proton radiography of dynamic electric and magnetic fields in laser-produced high-energy-density plasmas

Physics of Plasmas ◽

10.1063/1.3096781 ◽

2009 ◽

Vol 16 (5) ◽

pp. 056304 ◽

Cited By ~ 19

Author(s):

C. K. Li ◽

F. H. Séguin ◽

J. A. Frenje ◽

M. Manuel ◽

D. Casey ◽

...

Keyword(s):

Energy Density ◽

Magnetic Fields ◽

High Energy ◽

High Energy Density ◽

Proton Radiography ◽

Electric And Magnetic Fields ◽

High Energy Density Plasmas

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Time-Resolved Measurements of Turbulent Mixing in Shock-Driven Variable-Density Flows

Scientific Reports ◽

10.1038/s41598-019-56736-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

John Carter ◽

Gokul Pathikonda ◽

Naibo Jiang ◽

Josef J. Felver ◽

Sukesh Roy ◽

...

Keyword(s):

Large Scale ◽

Scalar Fields ◽

High Energy ◽

Variable Density ◽

High Energy Density ◽

Time Resolved ◽

Vortex Merging ◽

Recent Developments ◽

Spatio Temporal ◽

Large Scale Simulations

AbstractRecent developments of burst-mode lasers and imaging systems have opened new realms of simultaneous diagnostics for velocity and density fields at a rate of 1 kHz–1 MHz. These enable the exploration of previously unimaginable shock-driven turbulent flow fields that are of significant importance to problems in high-energy density physics. The current work presents novel measurements using simultaneous measurements of velocity and scalar fields at 60 kHz to investigate Richtmyer-Meshkov instability (RMI) in a spatio-temporal approach. The evolution of scalar fields and the vorticity dynamics responsible for the same are shown, including the interaction of shock with the interface. This temporal information is used to validate two vorticity-deposition models commonly used for initiation of large scale simulations, and have been previously validated only via simulations or integral measures of circulation. Additionally, these measurements also enable tracking the evolution and mode merging of individual flow structures that were previously not possible owing to inherently random variations in the interface at the smallest scales. A temporal evolution of symmetric vortex merging and the induced mixing prevalent in these problems is presented, with implications for the vortex paradigms in accelerated inhomogenous flows.

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X-Ray Spectroscopy of Laser-Produced Plasmas

International Astronomical Union Colloquium ◽

10.1017/s025292110008581x ◽

1984 ◽

Vol 86 ◽

pp. 229-233

Author(s):

Robert L. Kauffman

Keyword(s):

High Energy ◽

Spectroscopic Studies ◽

Spectral Lines ◽

High Energy Density ◽

Stark Broadening ◽

Density Region ◽

Time Resolved ◽

X Ray ◽

Relative Line ◽

Time Histories

Laser-produced plasmas have some of the highest temperatures and densities obtainable in the laboratory. This offers the opportunity to perform spectroscopic studies in new temperature and density regimes under controlled laboratory conditions. Temperatures can range from greater than 1 keV to less than 1 eV, while densities range from less than 1020e−/cm3 to greater than 1023e−/cm3. X-ray spectroscopy has been an important tool in diagnosing these large ranges of temperature and density. Relative line intensities of resonance and satellite lines can be used to diagnose the lower densities and higher temperatures. (Galanti and Peacock 1975, Boilo et al. 1979) For the denser plasmas Stark broadening is a good density diagnostic. (Yaakobi et al. 1977) Absorption spectroscopy measuring edge shifts had recently been used to probe the low temperature, high density region. These plasmas, with their high-energy density, are transient with total time scales ranging from 100 psec to greater than 1 nsec, depending on the laser driver pulse. In order to make detailed measurements from these plasmas, sensitive, time-resolved spectrographs have been developed. (Lewis et al. 1980, Kauffman et al. 1983) These spectrographs can measure time histories of spectral lines with resolving powers of 300 or greater and with time-resolutions of 20 psec. By using such instruments, studies of the dynamics of the plasma can be made.

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Modeling hydrodynamics, magnetic fields, and synthetic radiographs for high-energy-density plasma flows in shock-shear targets

Physics of Plasmas ◽

10.1063/1.5126149 ◽

2020 ◽

Vol 27 (1) ◽

pp. 012303 ◽

Cited By ~ 1

Author(s):

Yingchao Lu ◽

Shengtai Li ◽

Hui Li ◽

Kirk A. Flippo ◽

Dan Barnak ◽

...

Keyword(s):

Energy Density ◽

Magnetic Fields ◽

High Energy ◽

High Energy Density ◽

Plasma Flows ◽

Density Plasma

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Electrical conductivity of warm dense silica from double-shock experiments

Nature Communications ◽

10.1038/s41467-021-21046-1 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

M. Guarguaglini ◽

F. Soubiran ◽

J.-A. Hernandez ◽

A. Benuzzi-Mounaix ◽

R. Bolis ◽

...

Keyword(s):

Electrical Conductivity ◽

Dynamic Compression ◽

Experimental Studies ◽

High Energy ◽

Planetary Science ◽

Pressure Effects ◽

High Energy Density ◽

Hugoniot Curve ◽

Thermodynamic Conditions ◽

Reflectivity Data

AbstractUnderstanding materials behaviour under extreme thermodynamic conditions is fundamental in many branches of science, including High-Energy-Density physics, fusion research, material and planetary science. Silica (SiO2) is of primary importance as a key component of rocky planets’ mantles. Dynamic compression is the most promising approach to explore molten silicates under extreme conditions. Although most experimental studies are restricted to the Hugoniot curve, a wider range of conditions must be reached to distill temperature and pressure effects. Here we present direct measurements of equation of state and two-colour reflectivity of double-shocked α-quartz on a large ensemble of thermodynamic conditions, which were until now unexplored. Combining experimental reflectivity data with numerical simulations we determine the electrical conductivity. The latter is almost constant with pressure while highly dependent on temperature, which is consistent with simulations results. Based on our findings, we conclude that dynamo processes are likely in Super-Earths’ mantles.

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