Quantifying Reconnection*

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Quantifying Reconnection
NASA grant NAG5-10489

• Dana Longcope, Dave McKenzie
• Jonathan Cirtain, Jason Scott
• Montana State University

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Prototype of Solar-BReconnection Observation
TRACE SoHO Solar-A GOES

• New AR emerges near old AR
• Catalog interconnections (EUV/SXR TRACE/Yohko)
• Make a magnetic model (LOS M-gram SoHO/MDI)
• Interp data w.r.t. the model
• Learn about reconnection

Requires long series m-grams (low cadence) long
series EUV/SXR (hi cadence) T sensitivity 1 - 10
MK
3
AR emergence
CORONA (TRACE)
734
0000
1200
0000
1200
0000
Aug 10, 2001
Aug 11, 2001
AR9574
AR9570
PHOTOSPHERE (SoHO/MDI)
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Why this is reconnection
Tsuneta 1996
Reconnected flux
Emerged flux
9570
9574
Old flux
Baum Bratenahl 1976
It is NOT a flare
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Catalog Interconning loops
(Longcope et al. 2005)
Synthetic slit separating diff. ARs
5139 images _at_ 28 sec 700 Aug10 2359 Aug11 BG
subtracted
TRACE 171 images
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Lots of loops 900 ? 1400
Loops are bright features
Genl brightg
1st loop 1236
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Finding the loops

• Identify peaks
• in slit-intensity
• loop fw _at_ hm

25
22
23
26
24
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Finding the loops
Verify spatial correspond-ence w/
interconing loops
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Magnetic Model
movie
SoHO/MDI
Identify distinct regions with Bz gt 45 G
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Magnetic evolution
Series of m-grams
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Coronal Field
Interconnection (PF) Increasing
Inter-connecting flux
P051
AR9574
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Flux in 171 A loops
Each loop is a field-line bundle (flux tube)
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Flux in 171 A loops
Y Flux in potl model
A p(d/2)2
Flux if B0 120 G
Cummulative loop areas
d
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Reconnection observed
Heating 5 x 1026 erg/sec
1 GV
0.1 GV
Dy 1021 Mx
24 hour delay
Reconnn burst 1017 Mx/sec
emergence
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Heating then cooling
GOES 1-8 A
Reconnection burst
TRACE 171 A
loops
3hr cooling 7.5 MK -gt 1 MK
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Heating then cooling
movie
TRACE 171 A
GOES 1-8 A
Yohkoh SXT
EM
SXT filter ratio
?cool 0.3 hrs
Hot (7.5 MK) after reconnection
T
t 10 hrs
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Model of energy storage
Constrain Flux Y minimize energy
W
Wfce
DW
Wpot
Flux Constrained Equilibrium (Longcope 2002)
?W 1031 ergs
0
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Consequence of latency
GOES 1-8 A
GOES 0.5-4 A
Radiated power P 5 x 1026 erg/sec
Radiated energy 1031 ergs
DWFCE 1031
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Role(s) of Current Sheet
Releases DE I Dy 1028 ergs
1018 Mx of newly reconnected flux (1 of DY)
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Summary Reconnection Lessons

• AR emergence gt reconnection (unambiguous case)
• Reconnection in brief (6 hour) burst after
  delay of 24 hours
• Separator reconnection
• Produces scores of 1018 Mx loops
• Delayed reconnection gt storage
• of energy 1031 ergs