this is not another 12th may 1997
DESCRIPTION
Coronal dimming analysis of 13th May 2005 event. Gemma Attrill CfA/SAO. 12/05/97. 13/05/05. This is not another 12th May 1997. 13th May 2005 is more complex because it follows solar maximum: residue magnetic fields. Complexity reflected in the coronal dimmings. 2. - PowerPoint PPT PresentationTRANSCRIPT
• This is not another 12th May 1997.
• 13th May 2005 is more complex because it follows solar maximum: residue magnetic fields.
12/05/97 13/05/05
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Coronal dimming analysis of 13th May 2005 event Gemma Attrill CfA/SAO
Complexity reflected in the coronal dimmings
Intensity evolution (35 hr) selected regions
Quiet SunCoronal Hole
Data gap: 17:37 - 22:58 UT
1 2 3 4 5
6 7 8
Away from core 1
Away from core 2
Inte
nsity
Time
1
2
3
45
6
7 8
Existing coronal hole and extended dimming
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
Previous rotation
17th April
Pre-eruption
13th May
Post-eruption:13th May
Extended CH is there all the time.
But obscured by overlying loops pre-eruption.
These loops are removed during the eruption.
QuickTime™ and a decompressor
are needed to see this picture.
1
2
3
45
6
7 8Region + - Absolute Net
1 1.60E+21 -3.10E+21 4.70E+21 -1.50E+212 2.30E+21 -9.50E+20 3.25E+21 1.35E+213 2.10E+21 -1.40E+21 3.50E+21 7.00E+204 3.00E+21 -1.90E+21 4.90E+21 1.10E+215 2.60E+20 -6.20E+20 8.80E+20 -3.60E+206 4.00E+20 -1.30E+20 5.30E+20 2.70E+207 2.70E+20 -4.40E+20 7.10E+20 -1.70E+208 5.20E+19 -6.70E+19 1.19E+20 -1.50E+19
QuickTime™ and a decompressor
are needed to see this picture.
How are these loops involved in the eruption?
- Do they play a crucial role in making the footprint of the eruption so large-scale?
- Need to understand remote, secondary dimmings too.
Old MDI data - not recalibrated:
Small clues…
QuickTime™ and a decompressor
are needed to see this picture.
Plus global-scale coronal wave too!
QuickTime™ and a decompressor
are needed to see this picture.
QuickTime™ and a decompressor
are needed to see this picture.
10th April 8th May
Verification:
Dimming analysis 13/05/05Gemma AttrillMullard Space Science Laboratory
This is not another 12/05/97.
13/05/05 is more complex because it follows solar maximum: residue magnetic fields.
12/05/97 13/05/05
Dimming regions of 13/05/05
Attrill et al., (2006)
Selecting regions for analysis
Intensity evolution (35 hr) selected regions
Quiet SunCoronal Hole
Data gap: 17:37 - 22:58 UT
1 2 3 4 5
6 7 8
Away from core 1
Away from core 2
Inte
nsity
Time
1
2
3
45
6
7 8
Magnetic flux dimmings (20 G filter)
If dimmings 1 and 2 mark flux rope footpoints, then minimum magnetic flux of the flux rope:
((Absolute 1 + Absolute 2) / 2) = 3.98E+21 Mx
c.f. Yurchyshyn et al., (2006) use an Erupting Flux Rope model and Hu et al., (2006) use the Grad-Shafranov model:
Axial (torroidal) flux in ICME = 2.9E+21 Mx, 2.1E+21 Mx
Azimuthal (poloidal) flux in ICME = 4.4E+22 Mx, 4.2E+21 Mx
Our magnetic flux measurement (which is a minimum), is too large to be explained just by the axial (torroidal) magnetic flux. So the azimuthal (poloidal) magnetic flux is also required.
1
2
3
45
6
7 8
Region + - Absolute Net1 1.60E+21 -3.10E+21 4.70E+21 -1.50E+212 2.30E+21 -9.50E+20 3.25E+21 1.35E+213 2.10E+21 -1.40E+21 3.50E+21 7.00E+204 3.00E+21 -1.90E+21 4.90E+21 1.10E+215 2.60E+20 -6.20E+20 8.80E+20 -3.60E+206 4.00E+20 -1.30E+20 5.30E+20 2.70E+207 2.70E+20 -4.40E+20 7.10E+20 -1.70E+208 5.20E+19 -6.70E+19 1.19E+20 -1.50E+19
1
2
3
45
6
7 8
How do the dimmings form?
Region Net polarity1 -2 +3 +4 +5 -6 +7 -8 -
From SolarSoft Latest events archive. PFSS Derosa & Schrijver
3 47
1 2
Analysis of the evolution of the dimmings can give a lot of information (both quantitative & qualitative) regarding
the changing magnetic topology of the CME event.