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1

Influence of space charged particles on satellite optical communication system

Hou R., Zhao S., Xu J., Wu J., Li Y., Zhan S., Shi L., Fang S.

Optica Applicata

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2009

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Vol. 39, nr 2

251-265

EN

Although research of satellite optical communication system has been carried out for many years, there is scarce literature to comprehensively analyze the influence of space environment on satellite optical communication system. Different kinds of particles and fields exist in the space environment, including high energy charged particles, solar radiation, plasma environment, space fragment, etc. The Influence of space charged particles on satellite optical communication system was investigated in detail, which mainly related to single event upset (SEU), total dose effect and plasma environment. For SEU analysis the relation between single proton upset rate and satellite orbit was analyzed in detail. The reliability index of equipment based on SEU was proposed, the numerical calculation results have proved that the SEU effect was relatively less and corresponded to higher reliability of SRAM/MOS equipment under lower orbit altitude and inclination. For plasma environment analysis there is no obvious influence of plasma on laser signal transmission. But charging and discharging processes on satellite surface would lead to the malfunction of satellite communication system. The influence of charged particles and its related plasma on satellite optical communication system was investigated, which would be helpful for the design and the improvement of performance of satellite optical communication system.

2

Resonance acceleration of a charged particle in a laser beam and static magnetic field

Dubik A., Małachowski M. J.

Journal of Technical Physics

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2009

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Vol. 50, no 2

97-120

EN

Conditions at which the charged particles can be accelerated to the significant energies under interaction with the laser or maser radiation and the static magnetic field have been studied. The studies have been performed on the basis of the derived by the author's analytical solutions. With the example of an electron, the trajectory, velocity and kinetic energy as a function of the acceleration time have been shown. We have defined the maximal static magnetic field which was found to be appropriate to achieve the resonance condition in the acceleration process. At certain values of the magnetic field, the projections of the 3-dimensional trajectory onto the plane perpendicular to the axis show quite regular curves in the shape of epicycloids or hypocycloids with convex and concave bows, respectively. In the resonance region, there appears an increase in effectiveness of the energy transfer from the electromagnetic field to the accelerated particle and it can be realized simply through a very small increase of magnetic induction. The significant gain of the energy by the accelerated electron occurs only in the case of inversely directed laser beam velocity and the static magnetic field. The maximal energy can be increased by rising the laser beam or the magnetic field intensities. The energy gained by an electron depends on the acceleration time and it increases until the maximum energy is reached. The distance the electron covers to gain the maximal energy, depends on the intensities of the laser beam and the static magnetic field, and on the acceleration time. The analysis of acceleration process in the maser beam shows many advantages arising from the longer wavelength radiation emitted. The essential advantage is connected with the reduction of the static axial magnetic field intensity.

3

Ścisłe rozwiązanie relatywistycznych równań ruchu naładowanej cząstki w wiązce laserowej w obecności stałego, osiowego pola magnetycznego

Dubik A., Małachowski M. J.

Biuletyn Wojskowej Akademii Technicznej

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2009

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Vol. 58, nr 1

7-32

PL

W pracy przedstawiono wyniki teoretycznej analizy zachowania się naładowanej cząstki w polu elektromagnetycznym w wiązce laserowej oraz w stałym polu magnetycznym skierowanym osiowo względem wiązki laserowej. Wyniki w postaci graficznej uzyskano, korzystając z wyprowadzonych oryginalnych analitycznych wyrażeń. Weryfikację otrzymanych równań analitycznych przeprowadzono, rozwiązując wyjściowe równania różniczkowe metodą Runge-Kutta. Otrzymane analityczne równania umożliwiły ilościowe zobrazowanie za pomocą wykresów wpływu różnych parametrów na kształt, rozmiary, kierunek ruchu elektronu wzdłuż trajektorii, a także na jego energię kinetyczną. Przez zwiększanie natężenia pola elektrycznego wiązki laserowej można zwiększać rozmiary trajektorii zarówno w przypadku hipocykloid, jak i w przypadku epicykloid tzn. krzywych będących rzutem trajektorii na płaszczyznę (x, y). Ta zmiana jest proporcjonalna do zmiany amplitudy natężenia pola elektrycznego. Natomiast zwiększanie indukcji stałego, wzdłużnego pola magnetycznego prowadzi do zmniejszania rozmiarów trajektorii i zmian ich kształtów.

EN

The results of theoretical analysis of behaviour of charged particle in the electromagnetic field of laser beam in the presence of the axially directed static magnetic field are presented in the graphical form. The results have been obtained using the originally derived analytical equations. The equations have been verified by numerical solution of differential equations of motion using the Runge-Kutta method. The analytical equations with the aid of the proper curves enabled a quantitative illustration of the impact of different parameters on the shape, dimensions and the electron motion direction along the trajectory. By changing the intensity of the laser beam it is possible to change the dimension of the trajectories of hypocycloids as well as epicycloids which present the projection of the trajectories on the (x, y) plane perpendicular to the axis direction. This change was found to be proportional to the change of the electric field intensity. However, the increase in the static axial magnetic field leads to the decrease in the trajectory dimensions and the change of theirs shape.

4

Acceleration of charged particles in laser beam

Małachowski M., Dubik A.

Archives of Materials Science and Engineering

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2009

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Vol. 40, nr 2

98-103

EN

Purpose: The aim of this paper was to find parameters of the laser and maser beams in numerical ways with additionally applied external static axial magnetic field which satisfies the proper conditions for charged particle acceleration. Design/methodology/approach: The set acceleration was designed in order to obtain the possible high kinetic energy of the charged particles in the controllable manner. This was achieved applying a circularly polarized high intensity laser beam and a static axial magnetic field, both acting on the particle during the proper period. Findings: The quantitative illustrations of the calculation results, in a graphical form enabled to discuss the impact of many parameters on the acceleration process of the electrons and protons. We have found the impact of the Doppler Effect on the acceleration process to be significant. Increase in laser or maser beam intensity results in particle's energy increase and its trajectory dimension. However, increase in external magnetic field results in shrinking of the helical trajectories. It enables to keep the particle inside the laser beam. Research limitations/implications: Limits in the energy of accelerated particles arise from the limits in up-to-date available laser beam energy and the beam diameters. Originality/value: The authors show the parameters of the circularly polarized laser beam which should be satisfied in order to obtain the desired energy of the accelerated particles. The influence of the magnetic field strength is also shown.

5

Depozycja naelektryzowanych cząsteczek aerozolu w drogach oddechowych

Grabarczyk Z.J.

Przegląd Elektrotechniczny

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2006

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R. 82, nr 12

72-75

PL

W artykule przedstawiono aktualne poglądy na rolę ładunku elektrostatycznego cząsteczek fazy dyspersyjnej aerozolu w ich depozycji w drogach oddechowych człowieka i przedyskutowane niektóre inne, nie rozważane dotychczas efekty, mogące wspomagać depozycję cząsteczek naelektryzowanych dotychczas rozważane.

EN

The paper presents the contemporary scientific view of the role of the electrostatic charge of the aerosol particles in their deposition in human air ways and some other effects which could significantly enhance the electrical effect but not considered as far as today.