Study of moving striations in plasmas. IV. Electron-energy transfer and the determination of the electron thermal relaxation length

1968 ◽  
Vol 46 (19) ◽  
pp. 2193-2200 ◽  
Author(s):  
Michel G. Drouet
Keyword(s):  
Energy Transfer ◽  
Discharge Tube ◽  
Discharge Current ◽  
Small Amplitude ◽  
Positive Column ◽  
Relative Phase ◽  
Thermal Relaxation ◽  
Plasma Parameters ◽  
Relaxation Length

A general expression relating the small variations of the electron density, the electric field, and the electron temperature in a positive column is derived. It is shown that measurements of the variations of these plasma parameters in moving striations of small amplitude and in particular of the relative phase of these variations can be used to determine the thermal relaxation length for the electrons in a positive column.The value of the electron thermal relaxation length for a positive column in neon, with a pressure of 1 Torr, discharge current 26 mA, discharge-tube diameter 6.5 cm, is found to be approximately 1 cm.

Direct measurement of magnon temperature by magneto-optic Kerr effect in YIG

2021 ◽  
Author(s):  
fayuan zhang ◽  
Yuxi Qiao ◽  
Jiajia Wang ◽  
Wenjing Liu ◽  
Shan Qiao
Keyword(s):  
Kerr Effect ◽  
Thermal Relaxation ◽  
Relaxation Length ◽  
Spatially Resolved ◽  
Spin Seebeck Effect ◽  
The Difference ◽  
Iron Garnet ◽  
Insight Into ◽  
Magneto Optic

Abstract Magnon-phonon thermal relaxation holds a fundamental role in condensed matter physics, and the difference between local phonon and magnon temperature ΔTmp as an important part of this subfield was theoretically considered responsible for the spin Seebeck effect. Experimental determination of ΔTmp is necessary to give more insight into magnon-phonon coupling. Here we report spatially resolved measurements of magnon temperature performed by magneto-optic Kerr effect in yttrium iron garnet. Our results indicate a strong interaction between magnon and phonon subsystems in YIG with an upper limit of the phonon-magnon thermal relaxation length of 1.4 mm, and means this method is valid.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

scholarly journals Determination of energy-transfer distributions in ionizing ion-molecule collisions

2020 ◽  
Vol 1412 ◽  
pp. 152085
Author(s):  
S Indrajith ◽  
E Erdmann ◽  
J Chiarinelli ◽  
A Domaracka ◽  
M Łabuda ◽  
...  
Keyword(s):  
Energy Transfer

scholarly journals Numerical and Experimental Investigation of Longitudinal Oscillations in Hall Thrusters

Aerospace ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 148
Author(s):  
Vittorio Giannetti ◽  
Manuel Martín Saravia ◽  
Luca Leporini ◽  
Simone Camarri ◽  
Tommaso Andreussi
Keyword(s):  
Discharge Current ◽  
Fluid Model ◽  
Low Frequency ◽  
Hall Thruster ◽  
Hall Thrusters ◽  
Current Signal ◽  
Plasma Parameters ◽  
Plasma Properties ◽  
Breathing Mode ◽  
Spatio Temporal

One of the main oscillatory modes found ubiquitously in Hall thrusters is the so-called breathing mode. This is recognized as a relatively low-frequency (10–30 kHz), longitudinal oscillation of the discharge current and plasma parameters. In this paper, we present a synergic experimental and numerical investigation of the breathing mode in a 5 kW-class Hall thruster. To this aim, we propose the use of an informed 1D fully-fluid model to provide augmented data with respect to available experimental measurements. The experimental data consists of two datasets, i.e., the discharge current signal and the local near-plume plasma properties measured at high-frequency with a fast-diving triple Langmuir probe. The model is calibrated on the discharge current signal and its accuracy is assessed by comparing predictions against the available measurements of the near-plume plasma properties. It is shown that the model can be calibrated using the discharge current signal, which is easy to measure, and that, once calibrated, it can predict with reasonable accuracy the spatio-temporal distributions of the plasma properties, which would be difficult to measure or estimate otherwise. Finally, we describe how the augmented data obtained through the combination of experiments and calibrated model can provide insight into the breathing mode oscillations and the evolution of plasma properties.

Room temperature phosphorimetric determination of bromate in flour based on energy transfer

Talanta ◽  
2013 ◽  
Vol 116 ◽  
pp. 231-236 ◽  
Author(s):  
Mario Menendez-Miranda ◽  
Maria T. Fernandez-Argüelles ◽  
Jose M. Costa-Fernandez ◽  
Rosario Pereiro ◽  
Alfredo Sanz-Medel
Keyword(s):  
Energy Transfer ◽  
Room Temperature

scholarly journals Structural Determination of Lipid-bound ApoA-I Using Fluorescence Resonance Energy Transfer

2000 ◽  
Vol 275 (47) ◽  
pp. 37048-37054 ◽  
Author(s):  
Hui-hua Li ◽  
Douglas S. Lyles ◽  
Michael J. Thomas ◽  
Wei Pan ◽  
Mary G. Sorci-Thomas
Keyword(s):  
Energy Transfer ◽  
Fluorescence Resonance Energy Transfer ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Structural Determination ◽  
Fluorescence Resonance
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