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)– More particularly forcast those reaching the

Earth– iesFuture plans

Ne (cm-3) fp

low corona 108 100 MHz

~ 10 R ~ 104 ~ 1 MHz

~ 30 R ~ 1.5 103 ~ 350 kHz

~ 1 AU ~ 10 ~ 30 kHz

Radio emissions from the corona and

inner heliosphere

JLB / 2002.04.24 / ST-21 / EGS-Nice - 3 -

Coronal Mass Ejections

Fast and narrow CMES associated with short duration emissions(electron beams, typeIII).

Fast and large CMEs associated withcomplex radio emissions at meterwavelengths lasting >> 10 minutes.Also associated with flares

Radio detects these events above the solar limb and on-disk

Radio complex eventsover a large frequency rangeSimilarity 1MHz and 1-3 GHz Reiner et al. (2001,02)

Long duration >20 min

Origin in low corona

Flare/CME events

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) complex and 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 2004Pick et al, AdSR 35 1976 2005

Halo CME May 02 1998: Disk observations

Pohjolainen et al., 2001

October 28 2003 Halo CME CME

RH Nançay C2 LASCO

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)

October 28 2003Halpha Moreton wave

Moreton waves

Fast progression in latitudeFull extend: < 10 minSuccessive loop interactionsSuper-alfvenic disturbance

CME proxies

Angular extend Speed (3000km/s)

On-disk and limb CMEs

E

W

N

S

Duration (lateral spread)Indication on V

A new web site for radio monitoring A. Bouteille, R. Romagnan

M. 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/

++

Pair of long duration radio emissions

Post eruptive emissions of long duration dm-dam λ (NRH site) km bandwidth 300kHz drifting, Widely ≠ frequency range.Similar temporal, spectral profiles

Slow drifting BW 300KHz

PFFS extrapolation

Pairs of two continua not connected

If first harmonic emission, velocity of expansion 485 km/s and mean altitude of 5Rs near 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 originatesin region of interaction (sporadic m activity)

+

Low frequency continuum

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

• End

Limb events

Angular development < 10 min

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

164 MHz

in IP space

f ≈ R-1

fp = 9 √ Ne

kHz cm-3

Radio emissions from the inner

heliosphere

JLB / 2002.04.24 / ST-21 / EGS-Nice - 23 -