1. Solar Eruption Onset: Where Does the Action Begin?
Alphonse C. Sterling
UAT/NASA/MSFC/NSSTC/ISAS
A. Sterling, Feb 03

2. Introduction
Eruptions on the Sun involve the sudden release of large amounts of energy.
Where does the main energy release occur, and where are the key regions that are involved? Two possibilities:
Core region only, e.g., Moore & LaBonte, Moore et al. (“tether cutting); Chen; etc.
Far from the core also: Uchida (“quadruple model”); Antiochos et al. (“Breakout model”).
Objective: Compare Yohkoh and SOHO observations with predictions from Tether Cutting and Breakout models.
A. Sterling, Feb 03

3. Two Theories:
Tether cutting. Moore & Labonte (1980); Sturrock (1989); Moore et al. (1997; 2001).
Fundamentally bipolar.
Energy release via reconnection deep inside the “core field.”
Breakout model. Antiochos (1998); Antiochos et al. (1999).
Fundamentally multi-polar, with bipole core fields and restraining overlying fields.
Earliest energy release via slow reconnection at interface.
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4. (Moore et al. 2001)
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5. Antiochos
et al. (1999)
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6. Data: A Slow, Large-Filament Eruption
Large-scale, quiet region eruption.
Slow evolution (weak fields); can observe eruption in “slow motion.”
Test theories using timing studies.
Sterling, Moore, & Thompson (2001).
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9. Sterling, Moore, Thompson (2001)
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11. Sterling, Moore, Thompson (2001)
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12. No evidence for tether cutting prior to
filament launch (at least, very low EM
in EUV).
What about Breakout? Look for early
far-away activity with dimming images.
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17. Summary for This Event Quadruple, or quadrupole, structure
Tether Cutting seems to not work.
Might be consistent with Breakout.
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18. General Summary (Solar-B)
In at least some cases, the action begins far away from core.
Some observations with pointing offset from flare center could be important for understanding eruption onset.
A. Sterling, Feb 03