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SDO/AIA science plan: prioritization and implementation:

Five Objectives in 10 steps

I: C1/M8/C10 Transients: Drivers & Destabilization

Chair(s): Golub & Nitta

Status: [draft/review/final]

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Schedule

17 November 2005: draft sheets I, II to teams, requesting input for sheets III and IV

24 November 2005: completed sheets I-IV for review to teams, requesting input for sheets V-VI

8 December 2005: team input received for sheets V-VI 19 December 2005: draft of sheets VII-VIII to teams 9 January 2006: team comments received for sheets VII-

VIII 6 February 2006: draft ‘Science plans’ on meeting

website, with sheets IX-X filled out by team leads (or teams after telecons)

13-17 February 2006: discussions during science team meeting discuss and complete pages IX-X.

17 February: completed ‘Science plans’ on line.

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II: Science questions and tasks (1)

Primary scientific question: What types of magnetic field evolution lead

to instabilities and transients? What is the role of helicity injection and transfer? How does emerging flux interact with pre-existing

B? How is the stored magnetic released?

Is there a role for flux ropes? Where and how does reconnection occur?

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II: Science questions and tasks (2)

SDO/AIA science tasks: Task [1]: Unstable field configurations and

initiation of transients Find pre-eruption signatures of, e.g., tether-cutting or

breakout reconnection. Is braiding or sigmoid formation an eruption indicator? How do we best observe and use coronal dimming?

Task [2]: Evolution of transients Find signatures of inflow and outflow, cusps, patchiness

of reconnection. Determine how much flux participates in reconnection

episodes.D. McKenzie Overview Presentation

Task [3]: Early evolution of CMEs (Session C10) Task [4]: Particle acceleration (Session C10)

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III: Science context

Solar-B is likely to provide improved knowledge of locations of reconnection sites, inflows and outflows and local magnetic structure (modeled). Combination of XRT, EIS and B-extrapolations.

STEREO should provide improved knowledge of global configuration, in both plasma and field, and relation to properties of eruption. e.g., two magnetic configurations (normal and

inverse) vs. CME speed. Flux rope – ab initio vs. formed during event

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III: Science context (cont.)SDO will provide unique global coverage of: Pre-eruption coronal topology Magnetic field structure Event initiation and early evolution

Y. Su Presentation on shear change

How SDO data can be used: From B maps determine null points, separatrices or

QSLs. EUV channels provide imaging temperature (DEM) maps

of corona and its evolution. Locate and compare first brightenings and energy

release sites vs. global conditions (multi-polarity, helicity, etc,).

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III: Science context (cont.)

How to use SDO: Evolution of the full magnetic configuration. Determination of coronal B and comparison with EUV

observations. Observe T-slices of coronal structure, to follow all of

the plasmas as f(t). Need to know the large-scale field

Is “breakout” configuration a necessary condition? Systematic observations of pre-CME phase:

Flux tube present or not? Role of kink instability?Fludra/Harrison Presentation on CME Detection

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IV: Science investigation

Hurdles, bottlenecks, uncertainties: Parameters of flare trigger are unknown:

location, size, temperature, density. Consequences of energy release and particle

acceleration are visible (flare ribbons, chromospheric evaporation, heated plasma) but energy release site is not directly observed.

Large gap remains between B-extrapolations and observed coronal structure; not clear how to make progress.

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IV: Science investigation (cont.)

Hurdles, bottlenecks, uncertainties (cont.): What coronagraph observations will be

available? SOHO? STEREO? Other? Need to study tradeoffs for AIA: Number of

channels vs. image cadence vs. complexity of planning.