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Energy and Helicity B udget of Four S olar F lares and Associated Magnetic C louds.

Energy and Helicity B udget of Four S olar F lares and Associated Magnetic C louds. Maria D. Kazachenko, Richard C. Canfield, Dana Longcope, Jiong Qiu Montana State Universit y. Coronal Mass Ejections (CME) . CMEs. ICMEs. >1/3. Quiet sun structures. Active regions. Active regions.

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Energy and Helicity B udget of Four S olar F lares and Associated Magnetic C louds.

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  1. Energy and Helicity Budget of Four Solar Flares and Associated Magnetic Clouds. Maria D. Kazachenko, Richard C. Canfield, Dana Longcope, Jiong Qiu Montana State University

  2. Coronal Mass Ejections (CME) CMEs ICMEs >1/3 Quiet sun structures Active regions Active regions Non-Cylindrical structures Magnetic clouds (MC) Magnetic clouds (MC)

  3. Physical properties: CME vs MC ? • CME • axis orientation • magnetic flux • helicity • MC physical properties: • axis orientation • magnetic flux • helicity Compare! Modeled GOES magnetic energy radiated energy loss

  4. CME: flux rope formation To model CME flux rope properties we need to understand When are the flux ropes formed? Before flare Pre-existing During flare Formed in-situ • Emerge twisted • Formed by slow pre-flare magnetic reconnection • Fast magnetic reconnection during flare Low (1994), Fan & Gibson (2004), Leka et al. (1996), Abbett & Fisher (2003), van Ballegooijen & Martens (1989), Mackay and van Ballegooijen (2001), Forbes & Priest (1995), Antiochos et al. (1999), Lynch et al. (2004) Moore & LaBonte 1980, Mikic & Linker 1994, Demoulin et al. 1996, 2002; Magara et al. 1997; Antiochos et al. 1999; Choe & Cheng 2000; Nindos & Zhange (2002), Qiu et al. (2007), Longcope (2007).

  5. Work Outline Hypothesis: MCs originate from the ejection of locally in-situ formed flux ropes. Tools: Minimum Current Corona Model; MC, ribbon observations for four eruptive solar flares with MCs. • Analysis: Compare observed reconnection flux, energy, helicity with MCC model results. Results Comply with the scenario of in situ formed FR

  6. CSHKP. Minimum Current Corona Model 3D 2D Poloidal flux, P Flux rope MC) Plasmoid (CME) Separatrix Current sheet X-point Opened field lines Closed field lines Reconnection flux, rec Ribbons Minimum Current Corona Model, Longcope (1996) Carmichael (1964), Sturrock (1968), Hirayama (1974), Kopp and Pneuman (1976), Gosling (1990, 1995)

  7. Magnetic field evolution Magnetic field evolution in 40 hr. T0+40 hr T0 Set of magnetograms LCT Set of magnetic regions Magnetic point charge motions before May 13 2005 flare Set of magnetic point charges November & Simon (1988)

  8. Magnetic field topology Red: multiple domains Green: separator

  9. MCC: Magnetic stress buildup Tflare T0 Stress builds up Release Release 2 1 No reconnection Constant Domain fluxes Non-potentiality builds To preserve topology currents flow along separators Reconnection relaxes field to potential. Reconnection relaxes field to potential.

  10. MCC: Magnetic stress buildup Tflare T0 Stress builds up Release Release No reconnection 2 1 Tflare T0

  11. MC/flare properties: MCC Topology changes Topology changes Topology does not change Charge motion. No emergence. Currents build along separators 1 2 Field becomes potential Field becomes potential MDI, TRACE data Reconnection flux, r,MCC Flare magnetic energy, EMCC Flare Helicity, HMCC MCC + Longcope, Cowley (1996), Longcope & Magara (2004)

  12. MC/flare properties: MCC Reconnection flux, r,MCC Magnetic energy, EMCC Helicity, HMCC MDI, TRACE 1600 A + MCC MC/flare properties: Observations Reconnection flux, r,obs + TRACE 1600 A Ribbon motion Radiated energy loss, Eobs GOES 1-8 A Mewe loss function + L=1 AU MC poloidal flux P, Helicity Hobs Wind/ACE MC in situ data Grad-Shafranov and Lundquist fit +

  13. Flares studied Selection criteria • observations of both flare and MC • two successive flares (>M) in one AR • both close to the disk center • no significant flux emergence/cancellation

  14. Results: Magnetic flux • r ≈ [0.15, 0.40]*AR • r,MCC ≤ r,obs • MCC captures the lower limit of the reconnection flux. • p≤ r,obs • Supports CSHKP model (Qiu 2007). • Uncertainties: • TRACE ribbon edge identification, MC fitting (MC length, boundaries)

  15. Results: Energy • EMCC ≥ Eobs • MCC implies shearing/rotation provide enough energy to account for radiated energy loss. • Uncertainties: • GOES thermal radiated energy loss – lower limit on the energy (neglects thermal conduction and non-thermal energy). • MCC model estimates minimum energy. Longcope, DesJardins et al.(2010), Raftery et al. (2009), Longcope (2001)

  16. Results: Magnetic Helicity • HMCC ≈ Hobs • No preexisting twist required in these events • HMCC, Hobs < HAR • Uncertainties: • MC fitting (model-dependent, length, boundaries), fraction of H which goes into the flux rope (assume ½) Dasso (2003), (2006), Gibson (2008), Mackay (2006)

  17. Conclusions Main purpose of the study: Understand the FR formation and its relationship with the MC Tool, Data MCC model + observations for four eruptive solar flares with MCs Results: In these four events, the MCC model is able to account for the observed reconnection flux, FR helicity and flare energy. It suggests that: FRs are formed in situ within the AR, Flux emergence is relatively unimportant, No preexisting twist is required. Uncertainties: MC length, flux rope escape, total flare energy estimate. Kazachenko et al. 2009, 2010

  18. Acknowledgements • Richard Canfield, Dana Longcope, Jiong Qiu, Angela DesJardins, Richard Nightingale, QiangHu, NASA.

  19. Questions?

  20. Physical properties: MCC vs observations

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