1. SOHO-15, Sept. 8, 2004 Heating from Reconnection Quantified Dana Longcope Montana State University

2. SOHO-15, Sept. 8, 2004 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 MSU St. Andrews NSO Sac Peak

3. SOHO-15, Sept. 8, 2004 Reconnection Heating: Theory 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’n Taylor relax’n after QS evol’n van Ballegooijen 1985van Ballegooijen 1985 Dissipation of turbulent structure Dissipation of turbulent structure Parker 1988, Cargill 1993, 1994, …Parker 1988, Cargill 1993, 1994, … Nanoflares Nanoflares Longcope 1996, Aly & Amari 1997Longcope 1996, Aly & Amari 1997 QS Formation + rapid elimination of current sheets QS Formation + rapid elimination of current sheets =reconnection? (Parker 1972)

4. SOHO-15, Sept. 8, 2004 Heating from Reconnection Heating: P [ ergs/sec ] Reconnection  magnetic dissipation P rx [ ergs/sec ] P rx [ ergs/sec ] P = P rx P = P rx [Begging the question?]

5. SOHO-15, Sept. 8, 2004 Heating from Reconnection Heating: P [ ergs/sec ] Reconnection  flux transfer F [ Mx/sec ] F [ Mx/sec ] P = C F m P = C F m m >0 Reconnection heating 

6. SOHO-15, Sept. 8, 2004 Reconnection Heating P = C F m P = C F m 1.Quasi-static models: P = I qrx F P = I qrx F  = 1 Heyvaerts & Priest 1984 Longcope 1996 Aly & Amari 1997 … P ~ v P ~ v t D << t ev Units of constant: Amps

7. SOHO-15, Sept. 8, 2004 Reconnection Heating P = C F m P = C F m 2. Resistive dissipation: P = ( F ) 2 / R P = ( F ) 2 / R  = 2 Parker 1983, 1988 van Ballegooijen 1985 … P ~ v 2 P ~ v 2 t D ~ t ev Units of constant: Mhos

8. SOHO-15, Sept. 8, 2004 Quantifying Heating XBPs ARs Pevtsov et al. 2003

9. SOHO-15, Sept. 8, 2004 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 t rcyc

10. SOHO-15, Sept. 8, 2004 Quantifying Reconnection XBPs ARs Pevtsov et al. 2003

11. SOHO-15, Sept. 8, 2004 Whither Withbroe & Noyes? Quiet Sun: ~ 10 Mx/cm 2 (Lites 2002)  F x ~ 2 x 10 4 ergs/sec/cm 2 F ~ F x / c = 3 x 10 5 ergs/sec/cm 2 c ~ 0.1 (Withbroe & Noyes 1977) (Pevtsov et al. 2003)

12. SOHO-15, Sept. 8, 2004 Specific Case: AR 9574 PHOTOSPHERE CORONA TRACE 171A (10 6 K Plasma) 2001 Aug 11, 1:35 movie Emerging AR Emerging AR Interconnections Interconnections How much How much reconnection? reconnection? Longcope et al. 2004

13. SOHO-15, Sept. 8, 2004 P-spheric flux sources emergence begins

14. SOHO-15, Sept. 8, 2004 separator Coronal Model Interconnecting flux

15. SOHO-15, Sept. 8, 2004 Finding all the loops Peaks in a “slit”

16. SOHO-15, Sept. 8, 2004 Separatrices enclose loops

17. SOHO-15, Sept. 8, 2004 Reconnection observed Y Flux in pot’l model 24 hour delay Burst of reconnection 10 16 Mx/sec = 100 MV (Longcope et al. 2004)

18. SOHO-15, Sept. 8, 2004 Energy release Transfer flux DF Liberate energy D W D W ~ DF I qrx Dissipation? (NO) I ~ 3 x 10 10 A

19. SOHO-15, Sept. 8, 2004 Quiet Sun Case: XBP1 TRACE & SOI/MDI observations 6/17/98 (Kankelborg & Longcope 1999)

20. SOHO-15, Sept. 8, 2004 Quantifying Reconnection   Poles   Converging: v = 218 m/sec   Potential field: - bipole - changing  1.6 MegaVolts (on separator)

21. SOHO-15, Sept. 8, 2004 Surveys of XBPs  Archival SOHO data  EIT + MDI images  Visually ID XBPs in EIT 195A in EIT 195A  Extract bipole prop’s from 12 MDI prop’s from 12 MDI images (@15min) images (@15min) (Longcope et al. 2000, Aver & Longcope 2005)

22. SOHO-15, Sept. 8, 2004 Surveys of XBPs v d vrvr F+F+ F=( F + +F - )/2 t=d/vrt=d/vr (Aver & Longcope 2005) 149 XBPs 15 o

23. SOHO-15, Sept. 8, 2004 I qrx =10 11 A B 0 =10 G 1 G Convergingbipoles: P strongly correlates w/ reconn’n rate proxies Divergingbipoles: No Corr’n (Aver & Longcope 2005) F/t vrFvrF P P

24. SOHO-15, Sept. 8, 2004 Converging vs. Diverging convergence(closing)divergence(opening) reconnected flux time

25. SOHO-15, Sept. 8, 2004 Coronal recycling time (Close, Parnell, Longcope & Priest 2004) 50 MDI m-grams @ 15 min Identify sources Identify sources Coronal field from Coronal field from potential extrap’n potential extrap’n 240 Mm x 240 Mm quiet Sun region quiet Sun region

26. SOHO-15, Sept. 8, 2004 Coronal recycling time y i = interconn- ecting flux in domain i Flux balance: F a = p-spheric Flux in source a Change over Dt submergence/emergence Coronal reconnection “All flux goes somewhere”

27. SOHO-15, Sept. 8, 2004 Coronal recycling time Recycling by emergence or submegence Recycling by reconnection ~ 15 hours 3 hours 1.4 hours (cf. Hagenaar et al. 2003) et al. 2003) 2 diff. methods of elimating S i

28. SOHO-15, Sept. 8, 2004 Summary Heating of individual structures: P ~ FHeating of individual structures: P ~ F Suggests Quasi-static reconnection heatingSuggests Quasi-static reconnection heating P = I qrx F with I qrx = 2 x 10 5 t rcyc P = I qrx F with I qrx = 2 x 10 5 t rcyc Emerging AR (9574):Emerging AR (9574): –Reconnection delayed by ~24 hours – F = 260 MV, I = 3 x 10 10 A –Heating after reconnection XBPs: F ~ 1 MV, I ~ 10 9 AXBPs: F ~ 1 MV, I ~ 10 9 A –Convergence/divergence dichotemy – t rcyc ~ 2 hours