Heating from Reconnection Quantified

1
Heating from ReconnectionQuantified

• Dana LongcopeMontana State University

2
Acknowledgments

• Erik Aver
• Jonathan Cirtain
• Charles Kankelborg
• Dave McKenzie
• Jason Scott
• Alexei Pevtsov
• Robert Close
• Clare Parnell
• Eric Priest
• NASA grant NAG5-10489
• NSF grant ATM 97227

MSU
NSO Sac Peak
St. Andrews
3
Reconnection Heating Theory

• Parker 1972, Parker1983
• Topological dissipation
• Tucker 1973, Levine 1974
• Dissipation _at_ current sheets
• Heyvaerts Priest 1984
• Taylor relaxn after QS evoln
• van Ballegooijen 1985
• Dissipation of turbulent structure
• Parker 1988, Cargill 1993, 1994,
• Nanoflares
• Longcope 1996, Aly Amari 1997
• QS Formation rapid elimination of current
  sheets

(Parker 1972)
reconnection?
4
Heating from Reconnection
Heating P ergs/sec
Reconnection ? magnetic dissipation
Prx ergs/sec
P Prx
Begging the question?
5
Heating from Reconnection
Heating P ergs/sec
Reconnection ? flux transfer F
Mx/sec
Reconnection heating ?
P C F m
mgt0
6
Reconnection Heating
P C F m

• Quasi-static models

tD ltlt tev
Heyvaerts Priest 1984 Longcope 1996 Aly Amari
1997
P v
P Iqrx F
m 1
Units of constant Amps
7
Reconnection Heating
P C F m
2. Resistive dissipation
Parker 1983, 1988 van Ballegooijen 1985
tD tev
P v2
P (F)2 / R
m 2
Units of constant Mhos
8
Quantifying Heating
Pevtsov et al. 2003
ARs
XBPs
9
Quantifying Reconnection

• What is F ?
• What is F ?
• Which field lines change?
• Where does the change occur?

Average Heating ? General setting assume avg.
field line is recycled once in time trcyc
10
Quantifying Reconnection
Pevtsov et al. 2003
ARs
XBPs
11
Whither Withbroe Noyes?
Quiet Sun ltBzgt 10 Mx/cm2
(Lites 2002)
? Fx 2 x 104 ergs/sec/cm2
(Pevtsov et al. 2003)
F Fx / c 3 x 105 ergs/sec/cm2
(Withbroe Noyes 1977)
c 0.1
12
Specific Case AR 9574
Longcope et al. 2004
PHOTOSPHERE
2001 Aug 11, 135
CORONA

• Emerging AR
• Interconnections
• How much
• reconnection?

movie
TRACE 171A (106 K Plasma)
13
P-spheric flux sources
emergence begins
14
Coronal Model
Interconnecting flux
separator
15
Finding all the loops
Peaks in a slit
16
Separatrices enclose loops
17
Reconnection observed
Y Flux in potl model
(Longcope et al. 2004)
24 hour delay
Burst of reconnection 1016 Mx/sec 100 MV
18
Energy release
I 3 x 1010 A
Transfer flux DF Liberate energy DW
DW DF Iqrx
Dissipation? (NO)
19
Quiet Sun Case XBP1
TRACE SOI/MDI observations 6/17/98 (Kankelborg
Longcope 1999)
20
Quantifying Reconnection

• Poles
• Converging v 218 m/sec
• Potential field
• - bipole
• - changing
• ? 1.6 MegaVolts
• (on separator)

21
Surveys of XBPs

• Archival SOHO data
• EIT MDI images
• Visually ID XBPs
• in EIT 195A
• Extract bipole
• props from 12 MDI
• images (_at_15min)

(Longcope et al. 2000, Aver Longcope 2005)
22
Surveys of XBPs
149 XBPs
vr
15o
v
d
(Aver Longcope 2005)
F
F( FF-)/2
td/vr
23
(Aver Longcope 2005)
P
Diverging bipoles No Corrn
B010 G
Converging bipoles P strongly correlates w/
reconnn rate proxies
1 G
P
Iqrx1011 A
F/t
vrF
24
Converging vs. Diverging
convergence (closing)
divergence (opening)
time
reconnected flux
25
Coronal recycling time
(Close, Parnell, Longcope Priest 2004)
240 Mm x 240 Mm quiet Sun region

• Identify sources
• Coronal field from
• potential extrapn

50 MDI m-grams _at_ 15 min
26
Coronal recycling time
Fa p-spheric Flux in source a
yi interconn-ecting flux in domain i
Flux balance
All flux goes somewhere
Change over Dt
submergence/emergence
Coronal reconnection
27
Coronal recycling time
Recycling by emergence or submegence
15 hours
(cf. Hagenaar et al. 2003)
3 hours 1.4 hours
Recycling by reconnection
2 diff. methods of elimating Si
28
Summary

• Heating of individual structures P F
• Suggests Quasi-static reconnection heating
• P Iqrx F with Iqrx 2 x 105 trcyc
• Emerging AR (9574)
• Reconnection delayed by 24 hours
• F 260 MV, I 3 x 1010 A
• Heating after reconnection
• XBPs F 1 MV, I 109 A
• Convergence/divergence dichotemy
• trcyc 2 hours