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1.
In the framework of a quasilinear theory we examine the interaction between thermal electrons and ion-cyclotron waves (ICW) in the outer plasmasphere of the earth. For this type of wave-particle interaction, a simplification of the quasilinear diffusion integral in a magneto-active plasma under plasmaspheric conditions is given. Under the assumption of a Maxwellian distribution of electrons we have calculated the collision frequency and the heating source as the electrons are scattered by ICW. The obtained values of intrinsic parameters of the outer plasmasphere may exceed greatly, accordingly, the Coulomb frequency of collisions and the heating source due to suprathermal electrons. ICW-heating causes the ionosphereward thermal flux to increase, and this must lead to an increase in electron temperature in lower-lying plasmaspheric regions and in the subauroral ionosphere. A quantitative estimation of the electron temperature for the hot zone, made in this paper, is consistent with available experimental data.  相似文献   

2.
The equatorial ring current is the symmetrical plasmaspheric drift current of energetic plasma trapped by the geomagnetic field. Assuming that, during a geomagnetic storm, the ring can exchange energy with other regions of the magnetosphere, a second-order differential equation must be considered as its dynamical expression, and contributions other than the solely solar-wind-induced electric field must express the forced input. The decay parameters of the recovery phase of the storm must be determined considering periods with Bz(IMF) Bz(IMF) 0.  相似文献   

3.
Summary The observations of the ACTIVE Project satellites in the interval of March 17–23, 1990 were analyzed for the purpose of studying the response of the outer ionosphere to the magnetic storm with SSC on March 20 at 22.43 UT. In particular, measurements of thermal plasma parameters were used, but VLF broadband measurements and data on energetic ion and electron fluxes in the range of 17.7–272 keV were also available. The results of this case study show that the observations in the morning sector at altitudes around 2000 km reflect well the state of the plasmasphere during enhanced activity, namely the depth to which the plasmasphere has been affected by enhanced magnetospheric convection. They also provide the possibility of monitoring the initial phase of recovery. The early evening observations of the plasma parameters in the outer ionosphere at altitudes of 500–1000 km indicate a distinct trough in electron concentration. In the dusk sector, the equatorward edge of this trough can be assumed to be the projection of the equatorial plasmapause. This, combined with the occurrence of electron temperature peaks and with the morning plasmapause position, enables one to judge whether the plasmaspheric bulge has formed and whether an inner plasmapause has occurred.  相似文献   

4.
Summary Quarter-gyrofrequency plasmaspheric emissions with spectral properties differing from those of discrete plasmaspheric emissions, usual in active intervals, have been observed by low-altitude Intercosmos 24 and Magion 2 satellites during periods in which geomagnetic activity decreases. Their occurrence in satellite records shows very good correlation with simultaneously observed subauroral electron temperature enhancements and increase of electron temperature anisotropyT e being larger than T e . An analysis of the observed wave characteristics is given. Propagation of the emissions within the plasmasphere is discussed. It is shown that the region where they are observed at low altitudes can be closely connected along geomagnetic field lines with the equatorial region of their origin.  相似文献   

5.
This paper discusses a mathematical model which is aimed at the interpretation of the effects by injections of chemically active gases into the ionosphere. A study is made of neutral-gas expansion processes as well as of processes associated with the formation of decreased plasma density regions, ionospheric holes. The spatial-temporal distribution of particles released during the transition to the diffusion regime is constructed using an approximate, analytic solution of the Boltzmann equation with the collision integral in the form of BGK, with proper allowance for gravitation and atmospheric inhomogeneity. The investigation of processes associated with the formation of ionospheric holes is carried out using a numerical model of ionosphere-plasmasphere coupling, in which the transfer equations for charged components are integrated along geomagnetic field lines. The purpose of the model is to calculate the electron density and temperature, ion composition and emission of a disturbed region in the 6300 Å line at ionospheric and plasmaspheric heights.  相似文献   

6.
Observations using the very large array (VLA) radio interferometer during the past five years have enabled the discovery of a new type of plasmasphere disturbance, the magnetic eastward-directed wave. Previous work indicated these disturbances were likely frozen to the geomagnetic field as determined from their azimuth distributions. This work provides a method to explain more accurately the azimuth distribution, thereby allowing the calculation of the disturbances location in the plasmasphere independently of the measured velocity. The measurable velocity due to corotation is calculated and subtracted from the measured trace velocity. This difference, or deviation from corotation, is attributed to electrodynamic convection; the measurement of plasmaspheric convection may lead to the eventual monitoring of mid-latitude electric fields. Disturbances are seen convecting predominantly westward, with the fastest having angular velocities greater than the anticorotating VLA line of sight. The direction of convection and conditions of observations indicate that the disturbances are likely the same phenomenon seen by the Los Alamos satellite beacon array.  相似文献   

7.
An analysis of total ozone from Hradec Králové (50.25°N, 15.21°E) and of radio wave absorption in the lower ionosphere at 1539 kHz (reflection point 50.3°N, 11.8°E) shows that there is no detectable effect of strong solar flares in total ozone, no correlation between total ozone and absorption on a day-to-day time scale, and that strong solar flares do not affect this correlation. Thus the long-term correlation of monthly average values (Alberca et al., 1996) is not reproduced on a day-to-day time scale, and the effects of strong geomagnetic storms in total ozone (Latovika et al., 1992; Mlch and Latovika, 1996) have no counterpart in effects of strong solar flares.  相似文献   

8.
Summary The vertical distribution of the contribution of the energy flux density due to the Alfvén(ordinary) wave, guided by the geomagnetic field(and propagating through the ionosphere to the Earth's surface) in the horizontal direction is demonstrated in the mechanism of the horizontal propagation of the Pc1 signal. The distribution with height is shown of the variations of the polarization characteristics of the propagating wave(e.g. the rotation of the polarization plane, changes in ellipticity, attenuation, etc.), which are the result of coupling in the denser layers of the low ionosphere in which also suitable isotropic(extraordinary) modes are generated. The results obtained using the method described in[4, 13] are demonstrated on a model of the daytime ionosphere under incidence of ordinaryL-modes, frequency f=0.3 Hz, and various meridional angles at the ionosphere.
auauma anmau uaa Pc1 naa m an¶rt;u ¶rt;u nmmu ma uu uma anauu maum n n¶rt; , anma u nmu. naa m an¶rt;u uu aamumu nuauu anma (nauau nmu nuauu, uu unmumu, amau u m.¶rt;.), m m ¶rt;mu au¶rt;mu na uu u . ¶rt; mum n¶rt;¶rt;u umn() ¶rt;. mam num m¶rt; [4, 13] ¶rt;mua ¶rt;u ¶rt; u nu na¶rt;uu a u L-¶rt; amm f=0,3 n¶rt; au u¶rt;uau au.
  相似文献   

9.
Summary On the basis of investigating 10 storms (1965–1967) good correlation was found between the density of the solar wind energy (2=1/2mNv2) and the intensity of the main phase of the geomagnetic storms, expressed in terms of the maximum decrease of the horizontal intensity (B=H/cos). The relation between 2, or Nv2, and B could then be used to determine the quantities and 0 ( is the factor expressing the increase in energy density in the magnetosphere, 0 is the energy density of the particles in a quiet magnetosphere). A comparison with the directly observed distribution of the energy density of the particles in the magnetosphere indicates that the computed value of 0 seems to be realistic. The magnitude of the factor will have to be checked again.  相似文献   

10.
Summary Magnetic variations were recorded along three profiles crossing the southeastern margin of the Bohemian Massif. The data were processed in order to get induction vectors (Wiesevectors) and in-phase and out-of-phase induction vectors (Schmucker-vectors). Several events of field variations were separated into external and internal parts. The same events were also treated by a physical-statistical approach. Taking into account these results, we were able to delineate a zone of electrical inhomogeneity. It is in close relation to the Moravo-Silesian lineament. The depth of the internal anomalous field source was estimated at 20 to 25 km.
¶rt;a u uuau n uu n nu, nu — u. u¶rt;uu ( u), n u u n¶rt; u n u¶rt;uu ( ), n ¶rt;u n uau u u u n au ¶rt; uu-uuu ¶rt; u ¶rt;¶rt;u na¶rt; nu -uu . ¶rt; au uu a n a u n¶rt; 20–25 .
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11.
a mam 10-mu u¶rt;au ¶rt;uauu nmu a anam. auum aam mua ¶rt;uu u nu amu uu, a , muu, u auauu n u mmu u uu umaa u ¶rt; nmu uuau.  相似文献   

12.
This work reviews some aspects of the ionospheric F-layer in the vicinity of the geomagnetic equator. Starting with a historical introduction, brief summaries are given of the physics that makes the equatorial ionosphere so interesting, concentrating on the large-scale structure rather than the smaller-scale instability phenomena. Several individual topics are then discussed, including eclipse effects, the asymmetries of the equatorial trough, variations with longitude, the semiannual variation, the effects of the global thermospheric circulation, and finally the equatorial neutral thermosphere, including superrotation and possible topographic influences.  相似文献   

13.
Summary A model, explaining the effect of air pressure changes in the space of the measuring system on the fine dial counter constant of the Worden and similar gravity meters, is presented. It is based on the changes of the bellows volume with compensating the gravity changes. It is shown that the resetting the gravity meter in the whole range has practically no influence on the fine dial counter constant.
u¶rt;a ¶rt;, na m uu ¶rt;au ¶rt;a nmam uum um a nm a umaauma ¶rt; u nuaum. ¶rt; aa a uu a ua umu uma nu nauu uu u mmu. aa, m nma ¶rt;uanaa um namuu um a uu nm a uma.
  相似文献   

14.
Summary The effectiveness of recording seismic phenomena in the Kruné hory (Mts.) region in NW Bohemia by selected stations in the CSR, GDR and Poland has been estimated. Magnitude isolines of the weakest earthquakes, which can be localized and detected with an 0.9 probability, were calculated on the basis of the level of seismic disturbances at the individual stations and of the empirical dependence of the attenuation of seismic waves with distance.
a a mum umauu uu u amu ¶rt; ana¶rt; uu uau mauu a mumuu , u a a uu n a m¶rt; mau u nuu auumu amau uu m amu u auma uuuu aum¶rt; a a mu, m mm 0.9 auuam u aum.
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15.
nuam mam uu auauaum n aumua ¶rt; a 9 n mau ¶rt; nu No V, na anam. ma uam a aa u¶rt;uu aau ¶rt; uu u mau anamau. m m u¶rt;uu u aauuaa amma aamumua aa ma. ¶rt;a a m¶rt; mau ¶rt; aumua u mm a¶rt;u n a m u mau. uamua aau ¶rt;m u mu ma, m m ¶rt;u u umu m n. maum aamumuu n nma mmuuu aauu aumau ¶rt; m ¶rt;- ¶rt;¶rt;muu mm ¶rt; nu u m¶rt; am.

A substantial part of this paper was presented at the IAGA symposium Relations between External and Internal Magnetic Variations, XVI. IUGG General Assembly, August–September 1975, Grenoble.  相似文献   

16.
Summary The secular positive acceleration of the Earth's rotation has been computed on the basis of the observed secular decrease of the second zonal harmonic[5]. It corresponds to the observed secular deceleration of the Earth's rotation which should be greater because of oceanic tides.
¶rt; u a¶rt;a u m aauu [5], u ¶rt;a num u au. m mmmu a¶rt;a u mu au u, m.. n¶rt; n m uu , ¶rt; m n auu nuua.
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17.
a au ¶rt;a a¶rt;u naam, m m uu anau n m aum u m u. aam u¶rt;a nuuu u u au am nmu m au. ¶rt;m nu¶rt;umu, m m m a mu u. n¶rt;mauau auumu aama u¶rt;a u um ¶rt; um aamu.  相似文献   

18.
a aam u¶rt;au m ua aum aauu nu¶rt;u ¶rt; u anam a ¶rt;mu uu mu amuma n nu aum nuuumu num a¶rt;a uu ma¶rt;uuma, a m um ¶rt;u n u-a nummu ¶rt;¶rt;. num naau, m mua n¶rt;um nu¶rt; u ma aamam. a n¶rt;a umnmau aauuu u a mumuu m auu,¶rt; umuu n aaumu u mu n¶rt;umu m uam au u a mam ¶rt;u n n¶rt;a.  相似文献   

19.
um nu-mau m nuuau u auumu m nm ma u. m mu u¶rt;uu¶rt;a m ma nuua u uu.  相似文献   

20.
Summary The motion of particles in a turbulent flow is described by means of algebraic physics. The initial concepts are structurally ordered groupoids, algebras of observables, logically dependent on them, with couplings and the non-canonic transition between two Hamiltonians. The non-canonic transition leads to the substitution of time t by a new parameter. Its real counterpart gives the lower limit of the size of the time step in the differential equation of transfer, based on the semi-empirical image of turbulent diffusion.
uu amu mm muu nua ¶rt;mau aau uuu. ¶rt;u nmuu m mm n¶rt;nnu¶rt;, uu m u auu a a¶rt;a u u auu n¶rt; ¶rt; ¶rt;aumuaau. auu n¶rt; nu¶rt;um a u t naam. ¶rt;mum aa n¶rt;m uau aa am au na, nua a nnuu au mm ¶rt;uuu.
  相似文献   

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