SOHO-15, Sept. 8, 2004

Heating from Heating from ReconnectionReconnection

QuantifiedQuantified

Dana LongcopeDana LongcopeMontana State UniversityMontana State University

SOHO-15, Sept. 8, 2004

Acknowledgments:Acknowledgments:• Erik AverErik Aver• Jonathan CirtainJonathan Cirtain• Charles KankelborgCharles Kankelborg• Dave McKenzieDave McKenzie• Jason ScottJason Scott• Alexei PevtsovAlexei Pevtsov• Robert CloseRobert Close• Clare ParnellClare Parnell• Eric PriestEric Priest

• NASA grant NAG5-10489NASA grant NAG5-10489• NSF grant ATM 97227NSF grant ATM 97227

MSUMSU

St. AndrewsSt. Andrews

NSO Sac PeakNSO Sac Peak

SOHO-15, Sept. 8, 2004

Reconnection Heating: Reconnection Heating: TheoryTheory

• Parker 1972, Parker1983: Parker 1972, Parker1983: “ “Topological dissipation”Topological dissipation”• Tucker 1973, Levine 1974Tucker 1973, Levine 1974 Dissipation @ current sheets Dissipation @ current sheets • Heyvaerts & Priest 1984Heyvaerts & Priest 1984 Taylor relax’n after QS evol’nTaylor relax’n after QS evol’n• van Ballegooijen 1985van Ballegooijen 1985 Dissipation of turbulent structureDissipation of turbulent structure• Parker 1988, Cargill 1993, 1994, … Parker 1988, Cargill 1993, 1994, … NanoflaresNanoflares• Longcope 1996, Aly & Amari 1997Longcope 1996, Aly & Amari 1997 QS Formation + rapid elimination of current sheetsQS Formation + rapid elimination of current sheets

=reconnection=reconnection??

(Parker 1972)(Parker 1972)

SOHO-15, Sept. 8, 2004

Heating from Heating from ReconnectionReconnection

Heating:Heating: P P [ ergs/sec ][ ergs/sec ]

Reconnection Reconnection magnetic magnetic dissipationdissipation

PPrxrx [ ergs/sec ][ ergs/sec ]

P = PP = Prxrx[Begging the question?][Begging the question?]

SOHO-15, Sept. 8, 2004

Heating from Heating from ReconnectionReconnection

Heating:Heating: P P [ ergs/sec ][ ergs/sec ]

Reconnection Reconnection flux transferflux transfer

[ Mx/sec ][ Mx/sec ]

P = P = CC >0>0ReconnectionReconnection

heating heating

SOHO-15, Sept. 8, 2004

Reconnection HeatingReconnection Heating

P = P = CC

1.1. Quasi-static models:Quasi-static models:

P =P = I Iqrxqrx

dtP

= 1= 1

Heyvaerts & Priest 1984Heyvaerts & Priest 1984Longcope 1996Longcope 1996Aly & Amari 1997Aly & Amari 1997……

P ~ vP ~ v

DD << << evev

Units of constant: AmpsUnits of constant: Amps

SOHO-15, Sept. 8, 2004

Reconnection HeatingReconnection Heating

P = P = CC

2. Resistive dissipation:2. Resistive dissipation:

P =P = (())22 / R/ R

dVP2

E

= 2= 2

Parker 1983, 1988Parker 1983, 1988van Ballegooijen 1985van Ballegooijen 1985……

P ~ vP ~ v22

DD ~ ~ evev

Units of constant: MhosUnits of constant: Mhos

SOHO-15, Sept. 8, 2004

Quantifying HeatingQuantifying Heating

XBPs

ARs

3x 102L

Pevtsov et al. 2003

SOHO-15, Sept. 8, 2004

Quantifying ReconnectionQuantifying Reconnection• What is What is ??• What is What is ??

– Which field lines change?Which field lines change?– Where does the change occur?Where does the change occur?

Average Heating Average Heating General setting: General setting:

assume assume avg. fieldavg. field lineline is recycled once is recycled oncein time in time rcycrcyc

rcyc/~

SOHO-15, Sept. 8, 2004

Quantifying ReconnectionQuantifying Reconnection

rcyc/~

XBPs

ARsrcyc/~ qrxqrx IIP

A/s102/ 4rcyc qrxI

PLx

Pevtsov et al. 2003

3x 102L

SOHO-15, Sept. 8, 2004

Whither Withbroe & Whither Withbroe & Noyes?Noyes?

Quiet Sun: Quiet Sun: <<|B|Bzz||> ~ 10 Mx/cm> ~ 10 Mx/cm22

(Lites 2002)

FFxx ~ ~ 2 x 102 x 1044 ergs/sec/cmergs/sec/cm22

F ~ FF ~ Fxx / / = = 3 x 103 x 1055 ergs/sec/cmergs/sec/cm22

~ 0.1~ 0.1

(Withbroe & Noyes 1977)

(Pevtsov et al. 2003)

A/s102/ 5rcyc qrxI

SOHO-15, Sept. 8, 2004

Specific Case: AR 9574Specific Case: AR 9574PHOTOSPHERE

CORONA

TRACE 171A (10TRACE 171A (1066 K Plasma) K Plasma)

2001 Aug 11, 1:35

movie

• Emerging AREmerging AR• InterconnectionsInterconnections• How muchHow much reconnection?reconnection?

Longcope et al. 2004

SOHO-15, Sept. 8, 2004

P-spheric flux sourcesP-spheric flux sources

emergence emergence beginsbegins

SOHO-15, Sept. 8, 2004

separatorseparator

Coronal ModelCoronal Model

lA dInterconnecting fluxInterconnecting flux

SOHO-15, Sept. 8, 2004

Finding all the loops

Peaks in aPeaks in a““slit”slit”

SOHO-15, Sept. 8, 2004

SeparatricesSeparatricesenclose loopsenclose loops

SOHO-15, Sept. 8, 2004

Reconnection observedReconnection observed

Flux in pot’lFlux in pot’lmodelmodel

24 hour delay24 hour delay

Burst of reconnectionBurst of reconnection10101616 Mx/sec = 100 MV Mx/sec = 100 MV

(Long

cop

e e

t al. 2

00

4)

SOHO-15, Sept. 8, 2004

Energy releaseEnergy release

Transfer flux Transfer flux Liberate energy Liberate energy WW W ~ Iqrx

Dissipation? Dissipation? (NO)(NO)

I ~ 3 x 1010 A

SOHO-15, Sept. 8, 2004

Quiet Sun Case: XBP1Quiet Sun Case: XBP1

TRACE & SOI/MDI observations 6/17/98(Kankelborg & Longcope 1999)

SOHO-15, Sept. 8, 2004

Quantifying ReconnectionQuantifying ReconnectionPoles Converging: v = 218 m/secPotential field: - bipole - changing

1.6 MegaVolts (on separator)

Mx 101.1 19

Mx/sec 106.1 14Mx 106.0 19

SOHO-15, Sept. 8, 2004

Surveys of XBPsSurveys of XBPs Archival SOHO Archival SOHO datadata EIT + MDI imagesEIT + MDI images Visually ID XBPsVisually ID XBPs in EIT 195Ain EIT 195A Extract bipoleExtract bipole prop’s from prop’s from 12 12 MDIMDI images images (@15min)(@15min)

(Longcope et al. 2000,Aver & Longcope 2005)

SOHO-15, Sept. 8, 2004

Surveys of XBPsSurveys of XBPs

vd

vr

d/vr

(Aver

& L

on

gco

pe

200

5)

149 XBPs149 XBPs

1515oo

SOHO-15, Sept. 8, 2004

Iqrx=1011 A

B0=10 G1 GConvergingConverging

bipoles:bipoles:PP strongly stronglycorrelatescorrelates

w/ reconn’nw/ reconn’nrate proxiesrate proxies

DivergingDivergingbipoles:bipoles:No Corr’nNo Corr’n

(Aver & Longcope 2005)

vr

P

P

SOHO-15, Sept. 8, 2004

Converging Converging vs.vs. Diverging Divergingconvergenceconvergence

(closing)(closing)divergencedivergence(opening)(opening)

reconreconnected nected fluxflux

timetime

SOHO-15, Sept. 8, 2004

Coronal recycling timeCoronal recycling time(Close, Parnell, Longcope & Priest 2004)

50 MDI m-grams @ 15 min50 MDI m-grams @ 15 min

• Identify sourcesIdentify sources• Coronal field Coronal field fromfrom potential potential extrap’nextrap’n

240 Mm x 240 Mm240 Mm x 240 Mm quiet Sun regionquiet Sun region

SOHO-15, Sept. 8, 2004

Coronal recycling timeCoronal recycling time

ii = interconn- = interconn-ecting flux in ecting flux in domain domain ii

Flux balance:Flux balance:i

iiaa M ,

aa = p-spheric = p-spheric Flux in source Flux in source aa

)(,, iii

iaii

iaa RSMM ChangChangeeover over

submergence/submergence/emergenceemergence Coronal reconnectionCoronal reconnection

““All flux goes somewhere”All flux goes somewhere”

SOHO-15, Sept. 8, 2004

Coronal recycling timeCoronal recycling time

)( iii

i

RS

i

ise S

~/

i

i

R

~rcyc

Recycling Recycling by by emergence emergence or or submegencsubmegenceeRecycling Recycling by by reconnectioreconnectionn

~ 15 ~ 15 hourshours

3 hours3 hours

1.4 1.4 hourshours

(cf. Hagenaar (cf. Hagenaar et al. 2003)et al. 2003)

2 diff. methodsof elimating Si

A102 9qrxI

SOHO-15, Sept. 8, 2004

SummarySummary• Heating of individual structures:Heating of individual structures: P P ~~ • Suggests Quasi-static reconnection Suggests Quasi-static reconnection

heatingheating

PP == IIqrxqrx withwith IIqrxqrx == 2 x 102 x 1055 rcycrcyc

• Emerging AR (9574):Emerging AR (9574):– Reconnection delayed by ~24 hoursReconnection delayed by ~24 hours

– 260 MV, 260 MV, II == 3 x 103 x 101010 A A

– Heating Heating afterafter reconnection reconnection

• XBPs: XBPs: ~~1 MV1 MV, , II ~ ~ 101099 A A

– Convergence/divergence dichotemyConvergence/divergence dichotemy

– rcyc rcyc ~~ 2 hours2 hours