Probe measurements of electron temperature and density in strongly magnetized plasma

2000 ◽  
Vol 71 (9) ◽  
pp. 3382-3384 ◽  
Author(s):  
S. V. Ratynskaia ◽  
V. I. Demidov ◽  
K. Rypdal
Keyword(s):  
Electron Temperature ◽  
Magnetized Plasma ◽  
Probe Measurements

A magnetized plasma with very low electron temperature

2012 ◽  
Vol 21 (5) ◽  
pp. 055025 ◽  
Author(s):  
Shannon Dickson ◽  
Devin Konecny ◽  
Tyler Nickerson ◽  
Scott Robertson
Keyword(s):  
Electron Temperature ◽  
Magnetized Plasma

A new MHD model for Io's and Europa's plasma interaction

2020 ◽  
Author(s):  
Aljona Blöcker ◽  
Lorenz Roth ◽  
Nickolay Ivchenko ◽  
Emmanuel Chané ◽  
Ronny Keppens
Keyword(s):  
Heat Flux ◽  
Electron Temperature ◽  
Inelastic Collisions ◽  
Magnetized Plasma ◽  
Plasma Interaction ◽  
Complex Plasma ◽  
Electron Heat ◽  
Self Consistent ◽  
Physical Effects ◽  
Auroral Emissions

<p>Io and Europa are embedded in Jupiter’s magnetosphere and the moons’ surfaces and atmospheres interact with the surrounding moving magnetized plasma forming a complex plasma interaction. The interaction scenarios for both moons are characterized by inhomogeneities in the atmospheres from local outgassing. These inhomogeneities affect the electromagnetic environment but can also lead to localized features in the moons' auroral emissions. The moons’ aurora in turn is sensitive to the energy or temperature of the exciting electrons in the plasma. To simulate the interaction scenarios including atmospheric inhomogeneities and aurora generation, we expand the magnetohydrodynamic code MPI-AMRVAC by implementing a self-consistent description of the electron temperature and the electron density where the cooling by inelastic collisions between the magnetospheric electrons and the atmosphere, and the electron heat flux from the magnetospheric plasma to the moons’ ionosphere are included. Furthermore, the numerical schemes of MPI-AMRVAC are able to handle discontinuities that arise from the atmospheric inhomogeneities. Here, we demonstrate the implementation of the physical effects and first modeling results of Io’s and Europa’s plasma interaction with the advanced MHD code.</p>

Sustenance of inhomogeneous electron temperature in a magnetized plasma column

2015 ◽  
Vol 22 (9) ◽  
pp. 092107 ◽  
Author(s):  
S. K. Karkari ◽  
S. K. Mishra ◽  
P. K. Kaw
Keyword(s):  
Electron Temperature ◽  
Plasma Column ◽  
Magnetized Plasma

Characterization of Argon Plasma by Use of Optical Emission Spectroscopy and Langmuir Probe Measurements

2003 ◽  
Vol 17 (14) ◽  
pp. 2749-2759 ◽  
Author(s):  
Abdul Qayyum ◽  
M. Ikram ◽  
M. Zakaullah ◽  
A. Waheed ◽  
G. Murtaza ◽  
...  
Keyword(s):  
Electron Temperature ◽  
Flow Rate ◽  
Langmuir Probe ◽  
Gas Flow ◽  
Optical Emission ◽  
Filling Pressure ◽  
Emission Lines ◽  
Gas Flow Rate ◽  
Langmuir Probe Measurements ◽  
Probe Measurements

Spectroscopic and Langmuir probe measurements are presented to characterize the argon glow discharge plasma generated by a cost-effective 50 Hz AC power source. Optical emission spectra (400–700 nm) are recorded for different gas flow rates and filling pressures at constant power level. The plasma parameters (electron temperature and density) are deduced from the relative intensities of Ar-I and Ar-II lines. The variation in the intensity ratio of the selected emission lines, electron temperature and density is studied as a function of gas flow rate and filling pressure. Slight increase in the intensity ratio I2(426.62 nm )/I1(404.44 nm ) of the emission lines is observed whereas the electron temperature and density are found to decrease with increase in gas flow rate and filling pressure.

scholarly journals Drift-Alfvén fluctuations and transport in multiple interacting magnetized electron temperature filaments

2019 ◽  
Vol 85 (6) ◽  
Author(s):  
R. D. Sydora ◽  
S. Karbashewski ◽  
B. Van Compernolle ◽  
M. J. Poulos ◽  
J. Loughran
Keyword(s):  
Magnetic Field ◽  
Electron Temperature ◽  
Current Model ◽  
Outer Region ◽  
Wave Pattern ◽  
Plasma Potential ◽  
Magnetized Plasma ◽  
Low Energy Electrons ◽  
Convective Pattern ◽  
Set Up

The results of a basic electron heat transport experiment using multiple localized heat sources in close proximity and embedded in a large magnetized plasma are presented. The set-up consists of three biased probe-mounted crystal cathodes, arranged in a triangular spatial pattern, that inject low energy electrons along a strong magnetic field into a pre-existing, cold afterglow plasma, forming electron temperature filaments. When the three sources are activated and placed within a few collisionless electron skin depths of each other, a non-azimuthally symmetric wave pattern emerges due to interference of the drift-Alfvén modes that form on each filament’s temperature gradient. Enhanced cross-field transport from chaotic ( $\boldsymbol{E}\times \boldsymbol{B}$ , where $\boldsymbol{E}$ is the electric field and $\boldsymbol{B}$ the magnetic field) mixing rapidly relaxes the gradients in the inner triangular region of the filaments and leads to growth of a global nonlinear drift-Alfvén mode that is driven by the thermal gradient in the outer region of the triangle. Azimuthal flow shear arising from the emissive cathode sources modifies the linear eigenmode stability and convective pattern. A steady-current model with emissive sheath boundary predicts the plasma potential and shear flow contribution from the sources.

Plasma gradient effects on double-probe measurements in the magnetosphere

1995 ◽  
Vol 13 (2) ◽  
pp. 130-146 ◽  
Author(s):  
H. Laakso ◽  
T. L. Aggson ◽  
R. F. Pfaff
Keyword(s):  
Electron Temperature ◽  
Electron Density ◽  
Large Scale ◽  
Plasma Potential ◽  
Bias Current ◽  
Small Scale ◽  
Error Signal ◽  
Double Probe ◽  
Gradient Effects ◽  
Probe Measurements

Abstract. The effects on double-probe electric field measurements induced by electron density and temperature gradients are investigated. We show that on some occasions such gradients may lead to marked spurious electric fields if the probes are assumed to lie at the same probe potential with respect to the plasma. The use of a proper bias current will decrease the magnitude of such an error. When the probes are near the plasma potential, the magnitude of these error signals, ∆E, can vary as ∆E ~ Te(∆ne/ne)+0.5∆Te, where Te is the electron temperature, ∆ne/ne the relative electron density variation between the two sensors, and ∆Te the electron temperature difference between the two sensors. This not only implies that the error signals will increase linearly with the density variations but also that such signatures grow with Te, i.e., such effects are 10 times larger in a 10-eV plasma than in a 1-eV plasma. This type of error is independent of the probe separation distance provided the gradient scale length is much larger than this distance. The largest errors occur when the probes are near to the plasma potential. At larger positive probe potentials with respect to the plasma potential, the error becomes smaller if the probes are biased, as is usually the case with spherical double-probe experiments in the tenuous magnetospheric plasmas. The crossing of a plasma boundary (like the plasmapause or magnetopause) yields an error signal of a single peak. During the crossing of a small structure (e.g., a double layer) the error signal appears as a bipolar signature. Our analysis shows that errors in double-probe measurements caused by plasma gradients are not significant at large scale (»1 km) plasma boundaries, and may only be important in cases where small-scale (<1 km), internal gradient structures exist. Bias currents tailored for each plasma parameter regime (i.e., variable bias current) would o1q1improve the double-probe response to gradient effects considerably.

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