Energy and helicity b udget of four s olar f lares and associated magnetic c louds
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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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Energy and helicity b udget of four s olar f lares and associated magnetic c louds

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


Energy and helicity b udget of four s olar f lares and associated magnetic c louds

Coronal Mass Ejections (CME)

CMEs

ICMEs

>1/3

Quiet sun structures

Active regions

Active regions

Non-Cylindrical structures

Magnetic clouds (MC)

Magnetic clouds (MC)


Physical properties cme vs mc

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


Cme flux rope formation

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).


Work outline

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


Cshkp minimum current corona model

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)


Magnetic field evolution

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)


Magnetic field topology

Magnetic field topology

Red:

multiple domains

Green:

separator


Mcc magnetic stress buildup

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.


Mcc magnetic stress buildup1

MCC: Magnetic stress buildup

Tflare

T0

Stress builds up

Release

Release

No reconnection

2

1

Tflare

T0


Mc flare properties mcc

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)


Mc flare properties mcc1

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

+


Flares studied

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


Results magnetic flux

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)


Results energy

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)


Results magnetic helicity

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)


Conclusions

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


Acknowledgements

Acknowledgements

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


Questions

Questions?


Physical properties mcc vs observations

Physical properties: MCC vs observations


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