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Wave - particle s interaction in radiation belt region. Hanna Rothkaehl. Space Research Center, PAS Bartycka 18 A 01-716 Warsaw, Poland,.
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Wave-particles interactionin radiation belt region Hanna Rothkaehl Space Research Center, PAS Bartycka 18 A 01-716 Warsaw, Poland,
Electromagnetic emissions observed in the nearest Earth environment are superposition of natural emissions and various types of artificial noises. The magnetosphere-ionosphere-thermosphere subsystem is strongly coupled via the solar wind, electric and magnetic field topology, heat flows and small-scale interactions. Wave activity detected at low orbiting satellites can be also forced as a consequence of thunderstorm earthquake and volcanic activity. On the another hand wave particle interaction in the radiation belts region can be a sources of different type space plasma instabilities and in consequence can drive the changes of observed plasma particles energetic spectrum. • The aim of this paper is to present the overview of different type of events and models related to the high frequency wave and high energy particle interaction gathered at the of low orbiting satellite in the radiation belts region. The presented examples of physical processes in the radiation belts plasma can have a significantly influence for global changes in Earth plasma environment and could be of consequence for Space Weather modelling and services.
Electromagnetic pollution at top-side ionosphere- H. Rothkaehl 2003,2005 • Broad band emissions inside the ionospheric troughH. Rothkaehl,1997 ,Grigoryan 2003 • Whistler- gamma rays interaction related to the Earthquake, Rothkaehl, Kudela, Bucik 2005. HF wave interaction with energetic electrons
The + symbol marked the positions of radiations belts positions • The global distribution over Europe of mean value of the electromagnetic emission in the ionosphere in the frequency range 0.1-15 MHz on 30.03.1994 during strong geomagnetic disturbances, recorded by SORS-1 instrument on board the CoronasI satellite. The ACTIVE satellite electron data obtained in April 1990 The energy of electrons is E=44.2-69.9 keV.
THE EXAMPLE OF ELECTRON FLUX REGISTRATION AT MIDDLE LATITUDES IN DIFFERENT EXPERIMENTS, Grigoryan 2003) The electron fluxes under the inner radiation belt observed in different experiments since 1980th. Previous experiments – MIR station (see Grachev et al. (2002), SPRUT-VI experiment, altitude H= 350-400 km, electron energies Ee=0.3-1.0 MeV,), CORONAS-I satellite (see Kuznetsov et al (2002), altitude H~500 km, electron energies Ee>500 keV), OHZORA satellite (see Nagata et al. (1988), altitude H=350-850 km, electron energies Ee=190-3200 keV) revealed the existence of electron fluxes at L=1.2-1.8 (see Figure 1, panels A, B and C correspondingly). We analyzed electron flux data obtained from Active satellite. Electron flux enhancement under the inner radiation belt at L=1.2-1.8 is evident (see fig 1 and 2). Fig 2 Fig 1
THE DEPENDENCE OF ELECTRON FLUX DISTRIBUTIONS ON LEVEL OF GEOMAGNETIC ACTIVITY (see figure 4) AND MAGNETIC LOCAL TIME (see figure 5) DAY 06:00 – 21:00 MLT NIGHT 21:00–00:00-06:00 MLT Grigoryan 2003 • The observed dependences permit us to make the next conclusions: • the electron distribution depends on geomagnetic activity. The precipitation zones shift to larger longitudes both in north and south hemispheres during the disturbed periods of geomagnetic activity; • northern zone of electron precipitation exists mainly at night hours than at day hours; southern zone of electron precipitation shifts to larger longitudes at day hours, the latitudinal width of southern zone decreases at day hours; Fig 4 Fig 5
Human activity can perturb Earth's environment. • The Earth ionosphere undergoes various man-made influences: broadcasting transmitters, power station, power line and heavy industrial. • The observed broad band emissions are superposition of natural plasma emissions and man-made noises. • Pumping the electromagnetic waves from ground to the ionosphere and penetration of energetic particles from radiation belts can in consequence disturb top-side ionosphere. The scattering of super-thermal electrons on ion-acoustic or Langmuir turbulence is proposed as a mechanism of generation broad-band HF emissions.
The emissions coefficients for scattering of subthermal electron on the Langmuir jlk,and ion-acoustic jsk,turbulence for different ratio k vector for Te=8000 °K, Ti=1200 °K , ωpe=1.3MHz neo=0.1ne. The ratio of emissions coefficients S ,for scattering of subthermal electron on Langmuir and ion-acoustic turbulence for different ratio of Te to Ti for ionospheric plasma of ωpe=1.3MHz.
IONOSPHERIC TROUGH Instantaneous map of foF2 (x10 MHz) for 10 May 1992 at 22 UT with Kp*=7 given by the model and HF waves diagnosticsdata gathered on the board of APEX satellite. „Active” observation of electron flux (energies 44.2-69.9 keV).
Trough-plasmopause region Proposed mechanism ion-acoustic wave on the magnetic equator, energetization of electron at low altitude broad band HF emissions • MAGION 3
HF whistler- gamma rays interaction Global distribution of HF emission in the ionosphere in eastern hemisphere in the frequency range 0.1-2. MHz. The spectral intensity was integrated at times night 31.03.1994 during quiet condition and recorded by SORS instrument on board the CORONAS-I satellite. H. Rothkaehl 2005 The map of gamma rays fluxes in the energy range 0.12-0.32 MeV detected by SONG with a geometric factor of 0.55 cm2sr and with an acceptance angle of 30, on CORONAS-I satellite during the period from March 1994 through June 1994., K. Kudela, R. Bucik 2002
Ionospheric response to seismic activity • HF increasing of wave activity (whistler mode) • Increase of local electron density over epicentre • Wave-like change of electron density at F2 layers, enhancements of Es • Enhancement of gamma rays in 0.12-0.35 Mev • More pronouns effect during quit geomagnetic condition Parallel to the well-known effects related to the seismic activity in the top side ionosphere such as small-scale irregularities generated due to acoustic waves (Hegai et.al. 1997), and large-scale irregularities generated by anomalous electric field (Pulinets at al 2000), the modification of magnetic flux tube are also common features (Kim and Hegai 1997, Pulinets at al. 2002). So it seems that changes of the magnetic flux tube topology correlated with seismic activity can lead to the increase in the precipitation of energetic electron fluxes and, as a consequence, can yield excitation of the HF whistler mode., H.Rothkaehl 2005
LIGHTNING INDUCED HARD X-RAY FLUX ENHANCEMENTS: CORONAS-FOBSERVATIONS, Bucik 2005. VLF emissions triggered by lightning whistlers X rays enhanced emissions 30 - 500 keV