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Dec. 10, 2004 RHESSI/SOHO/TRACE
Pre-flare Energy StoragePre-flare Energy StoragePre-flare Energy StoragePre-flare Energy Storage
Current sheets Current sheets (YES)(YES)
Reconnection Reconnection (NO (NO thenthen YES) YES)
Dana LongcopeDana LongcopeMontana State UniversityMontana State University
Work supported by NASA NAG5-10489Work supported by NASA NAG5-10489
Thanks: Dave McKenzieThanks: Dave McKenzieJonathan CirtainJonathan Cirtain
Jason ScottJason Scott
Dec. 10, 2004 RHESSI/SOHO/TRACE
The Photospheric FieldThe Photospheric FieldThe Photospheric FieldThe Photospheric Field
• distribution of distribution of isolatedisolated sourcessources• evolution over ~ evolution over ~ daysdays• anchors coronal anchors coronal fieldfield
2001-08-10 12:51 UT 2001-08-10 12:51 UT 2001-08-11 17:39 UT 2001-08-11 17:39 UT
Dec. 10, 2004 RHESSI/SOHO/TRACE
The Coronal FieldThe Coronal FieldThe Coronal FieldThe Coronal Field
P07
P10
N09
N05
N01
P04
Total flux connecting Total flux connecting PPii N Njj: : ijij
7171
coronal connectionscoronal connections
4949
Dec. 10, 2004 RHESSI/SOHO/TRACE
The Coronal FieldThe Coronal FieldThe Coronal FieldThe Coronal Field
Potential Field: Potential Field: 0 Bsources
sources
Dec. 10, 2004 RHESSI/SOHO/TRACE
Quantifying FluxQuantifying FluxQuantifying FluxQuantifying Flux
• All flux connecting P07All flux connecting P07N01N01 enclosed by 2 enclosed by 2 separaticesseparatices• Intersect at Intersect at separatorseparator
separator
null
null
Dec. 10, 2004 RHESSI/SOHO/TRACE
Quantifying FluxQuantifying FluxQuantifying FluxQuantifying Flux
lA d71
close path
separator
• All P07All P07N01 lines enclosedN01 lines enclosed
• All flux connecting P07All flux connecting P07N01N01 enclosed by 2 enclosed by 2 separaticesseparatices• Intersect at Intersect at separatorseparator
Dec. 10, 2004 RHESSI/SOHO/TRACE
Model of energy storageModel of energy storageModel of energy storageModel of energy storageUnconstrained minimum: 0 B
Flux Flux (v)(v) linking poles linking poles
0
WWpotpot
WW
Dec. 10, 2004 RHESSI/SOHO/TRACE
Model of energy storageModel of energy storageModel of energy storageModel of energy storageConstrain Flux & minimize energy…
0
WWfcefce
WWpotpot
WW
WW
Flux Constrained Flux Constrained EquilibriumEquilibrium(Longcope 2002)(Longcope 2002)
Potential iff Potential iff (v) (v) =0=0
Dec. 10, 2004 RHESSI/SOHO/TRACE
Model of energy storageModel of energy storageModel of energy storageModel of energy storage
Lowest Lowest Energy w/ Energy w/
fixed fixed
Flux Flux Constrained Constrained EquilibriumEquilibrium(Longcope 2002)(Longcope 2002) • Current-freeCurrent-free
except …except …
Dec. 10, 2004 RHESSI/SOHO/TRACE
Model of energy storageModel of energy storageModel of energy storageModel of energy storageFlux Flux
Constrained Constrained EquilibriumEquilibrium(Longcope 2002)(Longcope 2002) • Current-freeCurrent-free
except …except …• Current SheetCurrent Sheet @ separator@ separator (())• Mag. EnergyMag. Energy in excess ofin excess of potentialpotential W(W())
Lowest Lowest Energy w/ Energy w/
fixed fixed
Dec. 10, 2004 RHESSI/SOHO/TRACE
Role(s) of Current SheetsRole(s) of Current SheetsRole(s) of Current SheetsRole(s) of Current Sheets
0
WWfcefce
WWpotpot
WW
WW
Energy storage:Energy storage:
W accumulatesW accumulatesprior to reconn’prior to reconn’burstburst
L
W2
2
Stored globallyStored globally
Dec. 10, 2004 RHESSI/SOHO/TRACE
Steady Reconnection?Steady Reconnection?Steady Reconnection?Steady Reconnection?
A01.0
)(
40
2
IS
BS
CS
CS 24
1 0 B
dICS lB
2/1CSArx S
= 4 months= 4 months
Sweet-Parker:Sweet-Parker:
Dec. 10, 2004 RHESSI/SOHO/TRACE
Role(s) of Current SheetsRole(s) of Current SheetsRole(s) of Current SheetsRole(s) of Current Sheets
0
WWfcefce
WWpotpot
WW
WW
Energy Energy RELEASE:RELEASE:
W accumulatesW accumulatesprior to reconn’prior to reconn’burst: burst: latencylatency
Rapidly releasedRapidly releasedvia via local local E field field
L
W2
2
Dec. 10, 2004 RHESSI/SOHO/TRACE
Role(s) of Current SheetRole(s) of Current SheetRole(s) of Current SheetRole(s) of Current Sheet
Site of Site of localizedlocalized
reconnectionreconnection
2 X 102 X 101818 Mx of newly Mx of newlyreconnectedreconnected flux flux
(1% of (1% of ))
Dec. 10, 2004 RHESSI/SOHO/TRACE
Role(s) of Current SheetRole(s) of Current SheetRole(s) of Current SheetRole(s) of Current Sheet
2 X 102 X 101818 Mx of newly Mx of newlyreconnected fluxreconnected flux
(1% of (1% of ))
ReleasesReleasesE ~ I E ~ I
~ 10~ 103131 ergs ergs
Dec. 10, 2004 RHESSI/SOHO/TRACE
Flux emergenceFlux emergenceFlux emergenceFlux emergence
AR9574 begins emergingAR9574 begins emerging@ 7:34 2001-08-10@ 7:34 2001-08-10
AR9570 remains
Coronal responseCoronal response
Dec. 10, 2004 RHESSI/SOHO/TRACE
Stack plotStack plotof inter-of inter-connectingconnectingloopsloops
Evidence of reconn’n Evidence of reconn’n latencylatency
Evidence of reconn’n Evidence of reconn’n latencylatency
loops
Dec. 10, 2004 RHESSI/SOHO/TRACE
Evidence of reconn’n Evidence of reconn’n latencylatency
Evidence of reconn’n Evidence of reconn’n latencylatency
GOES 1-8 AGOES 1-8 A
loopsloops
EUVEUV
loop EUVloop EUVemergence
TRACE 171 ATRACE 171 A
Dec. 10, 2004 RHESSI/SOHO/TRACE
Evidence of reconn’n Evidence of reconn’n latencylatency
Evidence of reconn’n Evidence of reconn’n latencylatency
reconnection
latencylatency
coolingcooling
emergence
Dec. 10, 2004 RHESSI/SOHO/TRACE
Evidence of reconn’n Evidence of reconn’n latencylatency
Evidence of reconn’n Evidence of reconn’n latencylatency
(v)(v)
from potential modelfrom potential model
from observed loopsfrom observed loops
latencylatency
latencylatency~24 hrs~24 hrs
flux transferflux transfer3.5 hrs3.5 hrs
= 10= 102121 Mx Mx
dd/dt = 10/dt = 1099 V V
Dec. 10, 2004 RHESSI/SOHO/TRACE
Consequence of latencyConsequence of latencyConsequence of latencyConsequence of latency
I = 1.3 x 10I = 1.3 x 101111 Amps Amps WWFCEFCE = 1.4 x 10 = 1.4 x 103131 ergsergs
= 10= 102121 Mx Mx
Dec. 10, 2004 RHESSI/SOHO/TRACE
Consequence of latencyConsequence of latencyConsequence of latencyConsequence of latencyGOES 1-8 AGOES 1-8 A
GOES 0.5-4 AGOES 0.5-4 A
Radiated power P ~ 5 x 10Radiated power P ~ 5 x 102626 erg/secerg/sec
Radiated energy10Radiated energy103131 ergsergs
2710I
WWFCEFCE = 10 = 103131
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