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Wave - particle s interaction s in radiation belt region

Wave - particle s interaction s in radiation belt region. Hanna Rothkaehl Space Research Center PAS, Poland. WG-2. Athens October 2005. Outline Electrons accelarated by ULF waves ( magnetosphere ) Electrons accelarated by VLF/ELF waves ( magnetosphere )

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Wave - particle s interaction s in radiation belt region

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  1. Wave-particles interactionsin radiation belt region Hanna Rothkaehl Space Research Center PAS, Poland WG-2 Athens October 2005

  2. Outline • Electrons accelarated by ULF waves (magnetosphere) • Electrons accelarated by VLF/ELF waves ( magnetosphere) • HF waves and energetic electrons (ionosphere)

  3. O’Brien et al. 2003 JGR

  4. The ULF waves seems to be a large potential store of energy (< 1%is going for energization the bulk of electrons) • Toroidal modes are related to the transverse ULF waves propagating waves along the magnetic field. • Poloidal modes related to the global compressionalULF waves associated with radial oscillation of the field line

  5. Mathie and Mann 2000,2001 morphological property of ULF(IMAGE)- MeV particle correlation(geosynchronous orbit) • Enhancements of Pc5(1-10 mHz) pulsation during – high level long live storm, extended 3-4 days, mainly in recovery phase. ULF pulsation during moderate solar speed conditions. • IMF Bz can affect on seed population keV electron • Acceleration process occurs over large L-shell maximizing at 4-6 L. Mathie,Mann, 2000

  6. Pc5 wave power decay exponentially with L decreasing Kelvin-Helmholtz instability • Increase decay rate of Pc5 wave power for faster solar wind speed • Alfven turbulance Efficiency of Pc5 activity -strong L function

  7. Models of acceleration electrons by ULF waves • Liu 1999. magnetic pumping by ULF waves • Summers 2000, transit –time dumping by fast mode MHD waves • Elkington 2003 ULF wave enhanced by radial diffusion

  8. Magnetic pumping by ULF waves Liu et al. JGR 1999. New mechanism of magnetic pumping - local pitch angle diffusion(time scale minutes, hours) -slowly radial diffusion (time scale days) The energy stored by MHD waves trough non adiabatic pitch angle scattering is used to energetization of electrons • Results: • The acceleration is most effective: • for the time scale of pitch angle scattering close to MHD waves period • for electrons starting with small pitch angle and return perpendicular to magnetic field. • Time scale for hole mechanism is in the range of hours- rapid acceleration.

  9. Radial diffusionElkingtown et al. 2003 Electrons are drifting in asymmetric compressed magnetic dipole The electrons are accelerate trough drift resonant interaction with ULF toroidal mode waves • Results: • The acceleration is most effective: • for theincreasing magnetospheric distortion • for ULF activity, background convection of electric field. • The acceleration occur as a radial drifting electrons outwards in dawn sector, and inward in dusk sector

  10. Transit time acceleration by fast-mode MHD waves Summers and Chun-yuJGR 2000. Transit-time damping related to the resonate electron interaction with low frequency oblique fast MHD mode,Pc4-Pc5 waves(magnetosonic) (broad band spectrum) via zero cyclotron harmonics(magnetic analogy of Landau damping) • Results: • The acceleration is most effective: • when transit time interaction between electrons and fast mode MHD waves turbulence are equal to period of waves

  11. Electron flux enhancements are related to ULF(mainly geosynchronous orbit) and VLF/ELF activity(mainly at L=4.5) O’ Brien 2003

  12. The VLF acceleration process is considerably more complicated than the ULF scenario. VLF acceleration is generally understood to proceed through resonance of a source population of ~100 keV electrons with strong VLF chorus activity which exists in the low density region just outside the plasmapause [e.g., Summers et al., 1998; Meredith et al., 2002a, 2002b]. Chorus activity is strongest on the dawnside beyond the plasmapause • For dense plasma ωpe>Ωe whistler mode and oblique magnetosonic near lower hybrid waves For low density plasma ωpe<Ωe LO RX Z whistler mode (Horne et al. 1999,2003)

  13. Meredith et.al. 2002 morphological property of VLF- MeV particle correlation CRESS satellite Local stochastic electron acceleration driven by whistler mode chorus The mechanism is more efficient for prolonged storm activity( 3 days during recovery phase).

  14. Models of acceleration electrons by VLF/ELF waves • Summers 1998, Relativistic theory of wave particle resonant diffusion • Horne et al.1999, 2003Resonant diffusion of electrons by whistler-mode chorus

  15. Horne et al.1999, 2003Resonant diffusion of electrons by whistler-mode chorus • Interaction with whistler chorus mode important for loss and acceleration process for electron • Most effective conditions for relativistic electron acceleration for low ωpe/Ωe • local acceleration process on day time scale • microburst(SAMPEX data). • Wave propagation affects to higher latitude , • e< 60 keV scatter to loss cone and trapped electron accelerate up to 1 MeV. • Acceleration at higher latitude more effective up to 3 Mev than equatorial process.

  16. Summreset al. 1988 Relativistic theory of wave particle resonant diffusion Resonant energy diffusion interaction for whistler( R mode) with electrons for low density plasma recovery phase EMIC (L mode) interaction with electrons with energy range ~ 1MeV, source of scattering loss for relativistic electrons main phase of the storm

  17. HF wave and energetic electrons • Electromagnetic pollution at top-side ionosphere- H. Rothkaehl 2003,2005 • Broad band emissions inside the ionospheric troughH. Rothkaehl,1997, Grigoryan 2003 • Whistler- gamma rays corelations interaction related to the Earthquake, Rothkaehl, Kudela, Bucik 2005.

  18. 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.

  19. The ACTIVE satellite electron data obtained in April 1990 The energy of electrons is E=44.2-69.9 keV. • 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 Coronas_I satellite.

  20. 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

  21. 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

  22. The emissions coefficients for scattering of superthermal 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 suerthermal electron on Langmuir and ion-acoustic turbulence for different ratio of Te to Ti for ionospheric plasma of ωpe=1.3MHz.

  23. Trough-plasmopause region Proposed mechanism ion-acoustic wave on the magnetic equator, energetization of electron at low altitude broad band HF emissions • MAGION 3

  24. 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).

  25. HF whistler- gamma rays interaction 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 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

  26. 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.

  27. 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

  28. LIGHTNING INDUCED HARD X-RAY FLUX ENHANCEMENTS: CORONAS-FOBSERVATIONS, Bucik 2005. VLF whistlers emissions triggered by lightning X rays enhanced emissions 30 - 500 keV

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