Diffusional mechanism of emission from a charged particle in dust particles

Astrophysics ◽  
1998 ◽  
Vol 41 (3) ◽  
pp. 289-298
Author(s):  
Zh. S. Gevorkian ◽  
V. V. Hambarian ◽  
A. A. Akopian
Keyword(s):  
Charged Particle ◽  
Dust Particles ◽  
Diffusional Mechanism

The Dynamics And Motions Of Dust Particles In Two And Three Negatively Charged Particle System: Theory And Modelling

2011 ◽  
Author(s):  
B. Nedaeeshakarab ◽  
R. Najafi Jabdaraghi ◽  
S. Sobhanian ◽  
Vladimir Yu. Nosenko ◽  
Padma K. Shukla ◽  
...  
Keyword(s):  
System Theory ◽  
Charged Particle ◽  
Particle System ◽  
Dust Particles

scholarly journals Diffusion Mechanism of Radiation of a Charged Particle on the Randomly Spaced Dust Grains in the X-Rays

1999 ◽  
Vol 194 ◽  
pp. 319-320
Author(s):  
Zh. S. Gevorkian ◽  
V. V. Hambaryan ◽  
A. A. Akopian
Keyword(s):  
Dielectric Constant ◽  
Charged Particle ◽  
Diffusion Mechanism ◽  
Wavelength Region ◽  
Mean Free Path ◽  
Characteristic Size ◽  
Dust Particles ◽  
X Rays ◽  
The Mean ◽  
A Charge

The theory of diffusion radiation of a charged particle on the fluctuations of the dielectric constant developed by Gevorkian can be explained as follows:A charge moving in a medium creates an electromagnetic field (pseudophoton) which is scattered on the fluctuations of the dielectric constant (here, dust particles) and converted into radiation. In the wavelength region (l « λ « L) (l is the mean free path of the photon in the medium, L is the characteristic size of the system) the main mechanism of the radiation is the diffusion of the pseudophoton (Gevorkian & Atayan 1990, Gevorkian 1992, Gevorkian 1993).

scholarly journals Particle-in-cell simulation of the effect of dust charge fluctuation on ion acoustic waves in a dusty plasma

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Suniti Changmai ◽  
Madhurjya P. Bora
Keyword(s):  
Charged Particle ◽  
Acoustic Wave ◽  
Dusty Plasma ◽  
Dust Particles ◽  
Charge Fluctuation ◽  
Ion Acoustic Wave ◽  
Particle In Cell ◽  
Dust Charge ◽  
Ion Acoustic ◽  
Dust Charge Fluctuation

AbstractA new hybrid-particle-in-cell (PIC)-Monte Carlo Collision (h-PIC-MCC) algorithm is presented here. The code correctly simulates the damping of ion acoustic wave due to dust charge fluctuation in a dusty plasma along with other kinetic effects such as Landau damping. In the model, on event of a collision between a charged particle and a dust particle, a randomised probability determines whether the charged particle is absorbed by the dust with the collision cross section being determined dynamically by the overall interaction scenario. We find that this method is versatile enough as it can also include the size and mass distribution for the dust particles, in addition to the charged species dynamics. As such, it can be adopted to study numerous phenomena that occur in diverse dusty plasma environments. We believe that the damping of the ion acoustic wave through dust charge fluctuation is being demonstrated, for the first time, with a PIC code, in this work.

Saturn's E, G and F rings: modulated by the plasma sheet

1984 ◽  
Vol 75 ◽  
pp. 597
Author(s):  
E. Grün ◽  
G.E. Morfill ◽  
T.V. Johnson ◽  
G.H. Schwehm
Keyword(s):  
Solar Wind ◽  
Direct Contact ◽  
Transport Processes ◽  
Time Variable ◽  
Dust Particles ◽  
Spatial Diffusion ◽  
Drag Forces ◽  
Orbit Perturbation ◽  
Time Variations ◽  
F Ring

ABSTRACTSaturn's broad E ring, the narrow G ring and the structured and apparently time variable F ring(s), contain many micron and sub-micron sized particles, which make up the “visible” component. These rings (or ring systems) are in direct contact with magnetospheric plasma. Fluctuations in the plasma density and/or mean energy, due to magnetospheric and solar wind processes, may induce stochastic charge variations on the dust particles, which in turn lead to an orbit perturbation and spatial diffusion. It is suggested that the extent of the E ring and the braided, kinky structure of certain portions of the F rings as well as possible time variations are a result of plasma induced electromagnetic perturbations and drag forces. The G ring, in this scenario, requires some form of shepherding and should be akin to the F ring in structure. Sputtering of micron-sized dust particles in the E ring by magnetospheric ions yields lifetimes of 102to 104years. This effect as well as the plasma induced transport processes require an active source for the E ring, probably Enceladus.

Analytical Electron Microscopy Characterization of Electric Arc Furnace Dust

1981 ◽  
Vol 39 ◽  
pp. 134-135
Author(s):  
J. R. Porter ◽  
J. I. Goldstein ◽  
D. B. Williams
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Electric Arc Furnace ◽  
Electric Arc ◽  
Dust Particles ◽  
Particle Analysis ◽  
Arc Furnace ◽  
Analytical Electron ◽  
Residual Elements ◽  
Industry Practice

Alloy scrap metal is increasingly being used in electric arc furnace (EAF) steelmaking and the alloying elements are also found in the resulting dust. A comprehensive characterization program of EAF dust has been undertaken in collaboration with the steel industry and AISI. Samples have been collected from the furnaces of 28 steel companies representing the broad spectrum of industry practice. The program aims to develop an understanding of the mechanisms of formation so that procedures to recover residual elements or recycle the dust can be established. The multi-phase, multi-component dust particles are amenable to individual particle analysis using modern analytical electron microscopy (AEM) methods.Particles are ultrasonically dispersed and subsequently supported on carbon coated formvar films on berylium grids for microscopy. The specimens require careful treatment to prevent agglomeration during preparation which occurs as a result of the combined effects of the fine particle size and particle magnetism. A number of approaches to inhibit agglomeration are currently being evaluated including dispersal in easily sublimable organic solids and size fractioning by centrifugation.

Improving soil remediation through characterization

1995 ◽  
Vol 53 ◽  
pp. 386-387
Author(s):  
E. C. Buck ◽  
N. L. Dietz ◽  
J. K. Bates
Keyword(s):  
Dust Particles ◽  
Radiochemical Analysis ◽  
Solid Product ◽  
Uranium Contamination ◽  
Physical Separation ◽  
X Ray ◽  
Rocky Flats ◽  
Remediation Strategies ◽  
Bearing Materials ◽  
X Ray Absorption

Operations at former weapons processing facilities in the U. S. have resulted in a large volume of radionuclidecontaminated soils and residues. In an effort to improve remediation strategies and meet environmental regulations, radionuclide-bearing particles in contaminant soils from Fernald in Ohio and the Rocky Flats Plant (RFP) in Colorado have been characterized by electron microscopy. The object of these studies was to determine the form of the contaminant radionuclide, so that it properties could be established [1]. Physical separation and radiochemical analysis determined that uranium contamination at Fernald was not present exclusively in any one size/density fraction [2]. The uranium-contamination resulted from aqueous and solid product spills, air-borne dust particles, and from the operation of an incinerator on site. At RFP the contamination was from the incineration of Pu-bearing materials. Further analysis by x-ray absorption spectroscopy indicated that the majority of the uranium was in the 6+ oxidation state [3].

Radiation of Charge Moving Between Two Planar Periodic Wire Structures

2020 ◽  
Vol 23 (1) ◽  
pp. 66-71
Author(s):  
E. A. Gurnevich ◽  
I. V. Moroz
Keyword(s):  
Angular Distribution ◽  
Charged Particle ◽  
Research And Development ◽  
High Power ◽  
Free Electron ◽  
Radiation Intensity ◽  
Free Electron Lasers ◽  
Radiation Sources ◽  
Power Radiation ◽  
High Power Radiation

The Smith-Purcell radiation of a charged particle moving in a periodic structure is analysed theoretically. The considered structure consists of two planar diffraction gratings with different periods which are formed by parallel conducting wires. The analytical expression for the spectral-angular distribution of radiation is obtained. It is shown that the angular distribution of radiation can be made narrower by using two gratings instead of one, and radiation intensity can be manipulated by parallel relative shift of gratings. The obtained results are of great importance for the research and development of high power radiation sources based on volume free-electron lasers.

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