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Solar radio emission at solar maximum. CME development in the corona M. Pick, D. Maia and Ch. Marqué LESIA, Observatoire de Paris. Cospar 2002. Context. Nançay Radioheliograph (NRH) Multiwavelength observations (dm-m) High cadence < second Radio survey

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Solar radio emission at solar maximum

Solar radio emission at solar maximum

CME development in the corona

M. Pick, D. Maia and Ch. Marqué

LESIA, Observatoire de Paris

Cospar 2002


Context
Context

  • Nançay Radioheliograph (NRH)

    • Multiwavelength observations (dm-m)

    • High cadence < second

  • Radio survey

    • NRH and WAVES/WIND spectrograph (dam-km)

    • Use for many objectives

  • Coordinated observations

    • SOHO, TRACE, ACE, WIND, YOHKOH, Ulysse and Ground facilities (Halpha and radio)

    • Interest of disk observations


Context1
Context

  • Flare/CME events

    • Non thermal emission

    • Energetic electrons tracers of B field

    • Search for weak emission often occulted by NT emission

  • CMEs in the absence of large flares

    • Association with noise storms (NT emission)

    • Thermal emission and eruptive prominences

      Radio signatures


CME lateral expansion

Fast progression in latitude

Full extend: 9 min ≥1000 km/s

Successive loop interactions

Super-alfvenic disturbance

Maia et al., 1999


Full expansion < 10 min.

Signatures of these interactions step by step. Follow in space and time CME progression

November 06 1997

Maia et al., 1999


On-disk event

Moreton wave

coronal shock wave

M-type IIAssociation

in time and space

Pohjolainen et al., 2001


Bastille event

Full expansion 15 min.

Maia et al. 2001


  • Proxies of CMEs

  • Lateral progression of CME development in the early stage

  • Full development reached within 10 min. or often less

  • Similar shape seen by NRH-LASCO(Gopalswamy and Kundu,1992)

  • Identification of different scenarios

  • Starting point :study of individual events


Other class of CME development

South part of the CME: Breakout type instability

Null point 26OOO km, B reconnection, MHD wave

triggers activity. S Loops pushing up and

interconnecting with multiple B systems.

North part of the CME (F sources):

Null points western part 6000km

Cospatial south loops

East and West Quasi

simultaneous

Coronal null point

Maia, Aulanier, S. J. Wang et al., 2002


Radio signature of

B reconfiguration

October 25, 2000


Dynamics of CMEs: Detection of weak NT emissions

Bastian et al., 2001: « Radio CME »

Maia et al., 2001Plasma front , CME-Driven shock


C2

NRH

  • Gyrosynchrotron emission

  • Radio V 1570 ± 390 km/s

  • LASCO V 980± 70 km/s

  • Deacceleration in the corona <4 Rs

  • (Gopalswamy et al., 02)

C3

C2


Thermal emission and cme development
Thermal emission and CME development

Type III like bursts

above the parasitic polarity

Radio depression

appears ~40 mn later

Dynamical continuity

radio depression and

CME substructures

Marqué et al., 2002



Conclusion
CONCLUSION

  • Multifrequency radio imaging observations

    • On-disk and limb behaviour of CME

    • Link with coronographic observations

    • Perspective :systematic studies using the survey

      CMEs, origin of energetic electron events…

  • Limitations

    • Need of high dynamic range

    • Hardly difficult to observe both weak and strong emission

    • Presently No sufficient frequency coverage

      • NEED for FASR



Data analysis coronal and ip radio signatures
DATA ANALYSISCoronal and IP Radio signatures

  • Wide spectral coverage

  • Radio source (dm-m)

  • 5 /11events: complex evolution

    (spectral, spatial and temporal)

WIND

DAM

09:28

NRH

18 February 2000


Radio signatures and cme
Radio signatures and CME

NRH: 09:19 UT

+

DAM

  • Source of electrons in region of interaction,

  • First shock is the triggering agent

  • Importance of the wide spectral range (Klassen, 01)


Role of moreton wave in flare cme development
Role of Moreton wave in flare/CME development

  • Moreton wave and coronal m-type II burst

  • Subsequent B interaction

Observations: agreement with P.F. Chen et al. (2002)

Piston-driven shock along envelope of CME

Legs Moreton wave

Moving wave-like (enhanced plasma region ahead) EIT wave

succesive opening of B (Delannée et al., 99)


Role of moreton wave in flare cme development1
Role of Moreton wave in flare/CME development

Flare/CME events involving multi-magnetic structures

Full expansion < 10 min.

Moreton waves: causal association with CMEs : lateral expansion

BUT NOT ALWAYS

Maia et al., 1999; Maia et al, 2001


Moreton waves and flare cme events
Moreton waves and Flare/CME events

East and West

Quasi simultaneous

F

A

D

E

C

Cospatial

south loops

Complex of activity

Filament eruption

Moreton wave, 1400 km/s


Moreton waves and flare cme events1
Moreton waves and Flare/CME events

South part of the CME:Breakout type instability

Null point 26OOO km, B reconnection, MHD wave triggers activity. S Loops pushing up and interconnecting with multiple B systems.

North part of the CME (F sources):

Null points western part 6000km

Alternatively, shock but no evidence in the north part

Moreton wave and eruptive prominence no significant role


October 14 1999

Maia, Aulanier, S. J. Wang et al., 2002


Radio event
Radio event

  • Faint type III-like bursts above the parasitic polarity: beginning of the eruption in EIT (slow evolution phase).

  • Radio depression to appear ~40 mn later (acceleration phase)

  • Dynamical continuity between radio depression and CME substructures.


South part of the CME: Breakout type instability

Null point 26OOO km, B reconnection, MHD wave

triggers activity. S Loops pushing up and

interconnecting with multiple B systems.

F

North part of the CME (F sources):

Null points western part 6000km

A

D

E

C

Cospatial

south loops

East and West

Quasi simultaneous


Dynamics of CMEs: Detection of weak NT emissions

Bastian et al., 2001: « Radio CME »

(Maia et al., 2001Plasma front , CME-Driven shock

15 April 2001


Moreton waves and flare cme events2
Moreton waves and flare/CME events

Disk event

  • Moreton wave

  • Pohjolainen, Maia, Pick, Vilmer et al., 2001


Detection of weak emissions

(Bastian et al.,2001)

CME-Driven shock

Plasma front

(Maia et al., 2001

CME Radio imaging


eruptive scenario (non thermal/thermal emission), observational continuity between eruptive site and coronagraph f.o.v.


Feb 28th 2002
Feb 28th 2002 observational continuity between eruptive site and coronagraph f.o.v.

  • Low energetical release event: ~B4 GOES event, faint type III like bursts.

  • Dark sigmoïd structure for the initial eruptive filament.

  • Eruption is triggered by the birth of a small parasitic polarity, a few hours before the D.B.

Ref: Marqué, Lantos, Delaboudinière, A&A, 2002, 387,317


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