# Presentation: 788616

## Related Solar Imaging and Near-Earth In-situ Observations of an ICME A. N. Fazakerley1, L.K. Harra1, J.L. Culhane1,L. van Driel-Gesztelyi1, 4, 5, E. Lucek2, S.A. Matthews1, C.J. Owen1, C. Mazelle3, A. Balogh2 and H. Rème3.1Mullard Space Science Laboratory, University College London2Imperial College, London 3Centre d’Etude Spatiale des Rayonnements, Toulousealso at 4Observatoire de Paris, Meudon and 5Konkoly Observatory, Budapest 

- Recently published by Fazakerley et al in GRL, 2005

## GOES 10: X-ray Light Curves

- We focussed on three events:
-   A: M class flare
-   B: Long duration C class flare  ***related to the ICME***
-   C: Series of three flares (GOES M – M – C) class

- A   B     C

**1. Solar Remote Sensing**
**    ****Observations**

**Notes:**
Are all these flares from that active region?

## SOHO:EIT

- (left) EIT 195 Å image of **Flare B** showing coronal arcade loops
- (right) EIT difference image showing “dimming regions” and aligned filament
-           channel

**SOHO:****EIT**

## SOHO:LASCO

**Halo CME ****associated ****with Flare B**

## SOHO: LASCO

**SOHO: ****LASCO**

- Cone Model:(**Michalek et al, 2003)**Estimation of CME speed, (**V ~ 910 km/s**), cone axis orientation, point of origin, using LASCO first/last detections of CME crossing the limb

## 2. Near Earth Observations: ACE, SOHO, Genesis, Cluster & Double Star TC-1 

- Solar
- Wind

**2. Near Earth Observations****: ****ACE, SOHO, Genesis, Cluster & Double Star TC-1**** **

- Cluster (15,-11,5)RE GSE

- TC-1 (12, 3.5, -2.1)RE GSE

-  ACE (230,-41,22)RE GSE

**Sun to Earth: 23,455 R****E**

- Genesis (243,77,51)RE GSE

**Notes:**
149 598 000 000 m = 1 AU = 23455 re

## ACE:Magnetic Field Instrument (MFI)Jan 15 to Feb 15 2004

- No shocks for a week before 22nd Jan

**ACE:****Magnetic Field ****Instrument (MFI)**Jan 15 to Feb 15 2004

- Significant magnetic
- storm at Earth

## Cluster:FGM, CIS

- Shock Normal Determination

- Earth

- XGSE

_*n*_

- Shock normal in the GSE frame
- (Cluster timing analysis)
- 	_*n*_* *=[0.905, -0.313, -0.288]
- tilted **at 25****°** to the Sun-Earth line
- This is consistent with the main
- body of the ejecta passing south
- and dawnward of the Earth
- Shock speed in the GSE frame:
- 	→ **740 km s****-1**** along the shock  **
**          ****normal**

- X,Z

- X,Y

- X,Y

- Earth

- Spacecraft in 200 km tetrahedron
- Data resolution 22 vec s-1

## Coronal Magnetic Fields

**Coronal Magnetic Fields**

**Magnetic polarity from MDI****Coronal arcade from EIT****Orientation of flux rope can be determined from these data ****(Martin, 2003)**

- 3. Combined Data Sets

## Near-Earth Magnetic Fields

**Before  01:35  Solar Wind****01:35 - 08:30  “sheath”****08:30 - 10:40  ICME Part (i)****10:40 & after  ICME Part (ii)**

**Near-Earth ****Magnetic Fields**

- Interpretation:**Flux rope (NNE-SSW orientation) erupts*****seen as ICME Part (ii)*****Overlaying coronal arcade material****(E-W orientation) carried ahead of ****flux rope - *****seen as ICME Part (i)***

## ACE:MFISWICS

- 180°

- 180°

- |B| (nT)

- Bz GSE (nT)

- Bx GSE (nT)

- By GSE (nT)

**ACE:****MFI****SWICS**

- np  (cm-3)

- Electron p.a. 372 eV

- He2+/H+  (%)

- O7+ /O6+

**“****Sheath”**
**Ahead **
**of CME**

**ICME part (ii)**

**High oxygen ionisation ratio, suggests high coronal source**

**ICME part (i)**

**Uni-directional electrons. **
**Later bi-directional trapped electrons**

**Notes:**
NOTE NOT A CLASSIC CLOUD – COMPLEX EJECTA

## SOHO: LASCO

- Expanding CME magnetic field reconnects with oppositely directed
- streamer field to produce open field-lines
- 	- temporary disconnection from Sun allows uni-directional electron streaming

## Summary

- ICME seen near-Earth Jan 22nd 2004
- Unambiguous identification of coronal source event (erupting flux rope)
- Determination of coronal magnetic fields
- Good match to in-situ magnetic fields
- The geomagnetic storm may have been predictable
- More effort needed on ICME interaction in IPM

## END OF TALK