Particle-in-cell simulations of electron acceleration by a simple capacitative antenna in collisionless plasma

We examine the electron acceleration by a localized electrostatic potential oscillating at high frequencies by means of particle‐in‐cell (PIC) simulations, in which we apply oscillating electric fields to two neighboring simulation cells. We derive an analytic model for the direct electron heating by the externally driven antenna electric field, and we confirm that it approximates well the electron heating obtained in the simulations. In the simulations, transient waves accelerate electrons in a sheath surrounding the antenna. This increases the Larmor radii of the electrons close to the antenna, and more electrons can reach the antenna location to interact with the externally driven fields. The resulting hot electron sheath is dense enough to support strong waves that produce high‐energy sounder‐accelerated electrons (SAEs) by their nonlinear interaction with the ambient electrons. By increasing the emission amplitudes in our simulations to values that are representative for the ones of the sounder on board the OEDIPUS C (OC) satellites, we obtain electron acceleration into the energy range which is comparable to the 20 keV energies of the SAE observed by the OC mission. The emission also triggers stable electrostatic waves oscillating at frequencies close to the first harmonic of the electron cyclotron frequency. We find this to be an encouraging first step of examining SAE generation with kinetic numerical simulation codes

The sources of modern linguistics terminological apparatus

In the paper by optionalitywe mean a speech modification functioning in the language, manifested in a peculiar deviation within the norm, which exists alongside with the codified literary obligatory variant in certain linguistic and extralinguistic conditions. The functional-dynamic method is one of the main methods we used in here. For the analysis of faculty, an attempt is made to use the studied parameters of such a linguistic phenomenon as variance. Thus, we suppose that the phenomenon of optionality is basically associated with the processes of changes in linguistic systems and is a factor in the dynamics of linguistic development

Pulsations Of Precipitating Energetic Electrons : Active Satellite Data

We present the patterns of high frequency energetic electron (∼ 20 to ∼ 300 keV) pulsations in middle latitudes, in subauroral and auroral regions, based on low altitude nearly polar orbiting satellite (Intercosmos-24, project ACTIVE) measurements. Two detectors with different orientations allowed the fluxes within and outside the loss cone to be compared. The trapped electrons do not exhibit the strong pulsations observed within the bounce loss cone. The pitch angle diffusion coefficient changes significantly on time scales comparable to or even shorter than the bounce period of electrons. The same is valid for changes of precipitating electron energy spectra. There are indications that both pitch angle and energy diffusion are in operation. VLF emissions at f < 3.5 kHz with a complicated structure are observed simultaneously with the electron pulsations, but there is no clear correlation between waves and particles. If the characteristics of the electron pulsations and VLF emissions are of a temporal character, they are qualitatively consistent with the models of nonlinear wave particle interactions, or with the concept of a flowing cyclotron maser. However, the pulsations may originate from fine spatial structure. Variability of the precipitation flux implies short time and/or small scale changes of ionization at altitudes down to 70 km. © 1998 Elsevier Science Ltd. All rights reserved.606643653Baker, D.N., Blake, J.B., Gorney, D.J., Higbie, P.R., Klebesadel, R.W., King, J.H., Highly relativistic magnetospheric electrons: A role in coupling to the middle atmosphere? (1987) Geophys. Res. Lett., 14, pp. 1027-1030Bryant, D.A., Courtier, G.M., Bennet, G., Equatorial modulation of electrons in a pulsating aurora (1971) J. Atmos. Terr. Phys., 33, pp. 849-858Coroniti, F.V., Kennel, C.F., Electron precipitation pulsations (1970) J. Geophys. Res., 75, pp. 1279-1288Datlowe, D.W., Imhof, W.L., Voss, D.H., Kilometer scale structures in auroral X rays arcs detected by combining satellite X-ray images with in situ energetic electron fluxes (1993) J. Geophys. Res., 98, pp. 9259-9266Davidson, G.T., Self-modulated VLF wave-electron interactions in the magnetosphere: A cause of auroral pulsations (1979) J. Geophys. Res., 84, pp. 6517-6523Davidson, G.T., Pitch angle diffusion in morningside aurorae. 1. The role of the loss cone in the formation of impulsive bursts of precipitation (1986) J. Geophys. Res., 91, pp. 4413-4427Davidson, G.T., Pitch angle diffusion in morningside aurorae. 2. The formation of repetitive auroral pulsations (1986) J. Geophys. Res., 91, pp. 4429-4436Davidson, G.T., Pitch angle diffusion and the origin of temporal and spatial structures in morningside aurorae (1990) Space Sci. Rev., 53, pp. 45-82Davidson, G.T., Chiu, Y.T., An unusual nonlinear system in the magnetosphere: A possible driver for auroral pulsations (1991) J. Geophys. Res., 96, pp. 19353-19362Demekhov, A.G., About the role of loss cone in the forming of pulsating regime of cyclotron instability of whistlers (1991) Geomagn. Aeron., 31, pp. 1099-1108Demekhov, A.G., Trakhtengerts, V.Yu., A mechanism of formation of pulsating aurorae (1994) J. Geophys. Res., 99, pp. 5831-5841Evans, D.S., Davidson, G.T., Voss, H.D., Imhof, W.L., Mobilia, J., Chiu, Y.T., Interpretation of electron spectra in morningside pulsating aurorae (1987) J. Geophys. Res., 92, pp. 12295-12306Hansen, H.J., Mravlag, E., Scourfield, M.W.J., Coupled 3- and 1.3-Hz components in auroral pulsations (1988) J. Geophys. Res., 93, pp. 10029-10034Imhof, W.L., Voss, H.D., Mobilia, J., Datlowe, D.W., Gaines, E.E., The precipitation of relativistic electrons near the trapping boundary (1991) J. Geophys. Res., 96, pp. 5619-5629Imhof, W.L., Voss, H.D., Mobilia, J., Datlowe, D.W., Gaines, E.E., McGlennon, J.P., Inan, U.S., Relativistic electron microbursts (1992) J. Geophys. Res., 97, pp. 13829-13837Imhof, W.L., Gaines, E.E., Inputs to the atmosphere from relative electrons (1993) J. Geophys Res., 98, pp. 13575-13580Imhof, W.L., Robinson, R.M., Collin, H.L., Wygant, J.R., Anderson, R.R., Simultaneous measurements of waves and precipitating electrons near the equator in the outer radiation belt (1994) J. Geophys. Res., 99, pp. 2415-2427Kudela, K., Matisin, J., Shuiskaya, F.K., Akentieva, O.S., Romantsova, T.V., Venkatesan, D., Inner zone electron peaks observed by the 'Active' satellite (1992) J. Geophys. Res., 97, pp. 8681-8685Kudela, K., Slivka, M., Martin, I.M., Jiricek, F., Triska, P., Shuiskaya, F.K., Strong fluctuations of energetic electrons at low attitudes (1997) Adv. Space Res., 20, pp. 499-503Kudela, K., Baláz, J., Strhársky, I., Štetiarová, J., Martin, I.M., Gladyshev, V., Shuiskaya, F.K., Klepikov, V., (1997) MEP1 Experiment: Scientific Tasks and Basic Characteristics, , Preprint of IEP SAS, Košice, April 1997, UEF-02-97Lepine, D.R., Bryant, D.A., Hall, D.S., A 2.2 Hz modulation of auroral electrons imposed at the geomagnetic equator (1980) Nature, 286 (5772), pp. 469-471Rycroft, M.J., Interactions between whistler-mode waves and energetic electrons in the coupled system formed by the magnetosphere, ionosphere and atmosphere (1991) J. Atmos. Terr. Phys., 53, pp. 849-858Sandahl, I., Eliasson, L., Lundin, R., Rocket observations of precipitating electrons over a pulsating aurora (1980) Geophys. Res. Lett., 7, pp. 309-312Sandahl, I., Pitch angle scattering and particle precipitation over a pulsating aurora - An experimental study (1984) Kiruna Geophys. Inst., Kiruna, Sweden, Rep., 185Sheldon, W.R., Benbrook, J.R., Bering, E.A., Rocket investigations of electron-precipitation and VLF waves in the Antarctic upper-atmosphere (1988) Rev. Geophys., 26, pp. 519-533Swift, D.W., Gorney, D.J., Production of very energetic electrons in discrete aurora (1989) J. Geophys. Res., 94, pp. 2696-2702Trakhtengerts, V.Yu., Mechanism of formation of pulsating auroras (1992) Proc. of the Int. Conf. on Substorms (ICS-1), Kiruna, Sweden, 23-27 March 1992, ESA SP, 335, p. 463. , May 1992Trakhtengerts, V.Yu., Magnetosphere cyclotron maser: Backward wave oscillator generation regime (1995) J. Geophys. Res., 100, pp. 17205-17210Tsuruda, K., Machida, S., Oguti, T., Kokubun, S., Hayashi, K., Kitamura, T., Saka, O., Watanabe, T., Correlations between the very low frequency chorus and pulsating aurora observed by low-light-level televison at L approx. 4.4 (1981) Can. J. Phys., 59, pp. 1042-1048Vampola, A.L., Gorney, D.J., Electron energy deposition in the middle atmosphere (1983) J. Geophys. Res., 88, pp. 6267-6274Yamamoto, T., On the temporal fluctuations of pulsating auroral luminosity (1988) J. Geophys. Res., 93, pp. 897-91

The sources of modern linguistics terminological apparatus [Opcionalidad como indicador del desarrollo del lenguaje]

In the paper by optionality we mean a speech modification functioning in the language, manifested in a peculiar deviation within the norm, which exists alongside with the codified literary obligatory variant in certain linguistic and extralinguistic conditions. The functional-dynamic method is one of the main methods we used in here. For the analysis of faculty, an attempt is made to use the studied parameters of such a linguistic phenomenon as variance. Thus, we suppose that the phenomenon of optionality is basically associated with the processes of changes in linguistic systems and is a factor in the dynamics of linguistic development. © 2018, Universidad del Zulia. All rights reserved

Valery Bryusov's world-modeling universals: the apperceptional base as the tool of world-modeling

The article is devoted to the analysis of world-modeling universals in the fantastic story "Night Journey" by Valery Bryusov through case study as one of the qualitative research methods. The study posed the issue of this work relationship with the novel "Fiery Angel" by the same author. Due to the laconic characterization of the space in which the narrator is located, the apperception base and the information in presupposition are of primary importance as a world-modeling instrument in this work.El artículo está dedicado al análisis de universales de modelado mundial en la fantástica historia "Viaje nocturno" de Valery Bryusov a través del estudio de casos como uno de los métodos de investigación cualitativa. El estudio planteó el tema de esta relación laboral con la novela "Fiery Angel" del mismo autor. Debido a la caracterización lacónica del espacio en el que se encuentra el narrador, la base de apercepción y la información en la presuposición son de primordial importancia como instrumento de modelado mundial en este trabajo

Upward high-energy field-aligned electron beams above the polar edge of auroral oval: observations from the SKA-3 instruments onboard the Auroral Probe (Interball-2)

A new phenomenon was found at the polar edge of the auroral oval in the postmidnight-morning sectors: field-aligned (FA) high-energy upward electron beams in the energy range 20–40 keV at altitudes about 3RE, accompanied by bidirectional electron FA beams of keV energy. The beam intensity often reaches more than 0.5·103 electrons/s·sr·keV·cm2, and the beams are observed for a relatively long time (~3·102–103s), when the satellite at the apogee moves slowly in the ILAT-MLT frame. A qualitative scenario of the acceleration mechanism is proposed, according to which the satellite is within a region of bidirectional acceleration where a stochastic FA acceleration is accomplished by waves with fluctuating FA electric field components in both directions.Key words. Ionosphere (particle acceleration; wave-particle interactions) · Magnetospheric physics (magnetosphere-ionosphere interactions)</p

Electron acceleration by MegaHertz waves during OEDIPUS-C

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