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The Space Weather Week

The Space Weather Week. Monique Pick LESIA, Observatoire de Paris. 13-17 November 2006. Interest of radio observations for CMEs More particularly forcast those reaching the Earth Proxies (Halo) Future plans Web site ( http://secchirh.obspm.fr)

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The Space Weather Week

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  1. The Space Weather Week Monique Pick LESIA, Observatoire de Paris 13-17 November 2006

  2. Interest of radio observations for CMEs • More particularly forcast those reaching the Earth • Proxies (Halo) • Future plans • Web site (http://secchirh.obspm.fr) • More particularly forcast those reaching the Earth • iesFuture plans

  3. Radio emissions from the corona and inner heliosphere JLB / 2002.04.24 / ST-21 / EGS-Nice- 3 -

  4. Coronal Mass Ejections Fast and narrow CMES associated with short duration emissions (electron beams, typeIII). Fast and large CMEs associated with complex radio emissions at meter wavelengths lasting >> 10 minutes. Also associated with flares Radio detects these events above the solar limb and on-disk

  5. Flare/CME events • Radio complex events over a large frequency range Similarity 1MHz and 1-3 GHz Reiner et al. (2001,02) • Long duration >20 min • Origin in low corona

  6. CME and Complex radio events • 26 complex radio events 20 events associated with shocks (type II-like features) • 26 associated with CMEs (also Cane, 2002); 17 halo CMEs; 7 Width> 100°. (reach Earth) • *Emitting radio sources (NRH meter λ) complexand spread over a large volume; onset of new sources • * Coronal processes, involving multiple B system participate in the eruption. Maia and Pick, ApJ, 609, 1082 2004 Pick et al, AdSR 35 1976 2005

  7. Halo CME May 02 1998: Disk observations Pohjolainen et al., 2001

  8. October 28 2003 Halo CME CME C2 LASCO RH Nançay • Radio imaging at 164 Mhz • traces the early CME development and the regions of • B interaction • The coronal wave and the CME encompasses most of the • solar disk (10 min)

  9. October 28 2003Halpha Moreton wave

  10. Moreton waves

  11. CME proxies On-disk and limb CMEs • Fast progression in latitude • Full extend: < 10 min • Successive loop interactions • Super-alfvenic disturbance W E N S • Angular extend • Speed (3000km/s) Duration (lateral spread) Indication on V

  12. A new web site for radio monitoringA. Bouteille, R. RomagnanM. Pick, M. Maksimovic, J. L. Bougeret, A. Lecacheux,(LESIA)C. Alissandrakis, X. Moussas , A. Hillaris (Greece)A. Vourlidas, R. Howard (NRL) CMEs (V, W, PA) Goal: one radio spectrum in combining data from different spectrographs (large freq. Range) -Nançay Radioheliograph (metric λ) - SECCHI CME summary (in near future) -Real time -NRH imaging link with the SWB, Royal Observatory http://secchirh.obspm.fr/

  13. Pair of long duration radio emissions Slow drifting BW 300KHz Post eruptive emissions of long duration dm-dam λ (NRH site) km bandwidth 300kHz drifting, Widely ≠ frequency range. Similar temporal, spectral profiles + + PFFS extrapolation

  14. Pairs of two continua not connected + Low frequency continuum • If first harmonic emission, velocity of expansion 485 km/s and mean altitude of 5Rsnear onset; CME has reached altitude of 6Rs (fp×r = 20kHz 1AU);13 UT 15 Rs • If plasma emission, kilometric source lower density than the source of metric continuum • Suggestion: Destabilization of loop system (Km) created by B interaction between expanding CME and neighbouring loops • Electrons radiating low freq continuum originates in region of interaction (sporadic m activity)

  15. Concluding remarks • Proxies • improve the characteristics : V , lateral expansion (statistical study) • Investigation on polarization • Futur work • S-Waves (STEREO) • Link with other sites • Survey SOHO 1997-to-day, in progress • Spectograph page > 16 hours • Includes spectral frequency range toward microwave

  16. End

  17. Limb events Angular development < 10 min

  18. 164 MHz • Electrons trace the expansion of • the arch system(~2500 km/sec) • Coronal wave develops along • flank of CME In lateral expansion

  19. Radio emissions from the inner heliosphere fp= 9 √ Ne kHz cm-3 in IP space f≈ R-1 JLB / 2002.04.24 / ST-21 / EGS-Nice- 23 -

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