An Emerging Flux Trigger Model for CMEs

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SOHO/SUMER Observations of Prominence
Oscillation before Eruption
P. F. Chen
Department of Astronomy Nanjing
University Nanjing 210093 China chenpf_at_nju.edu.cn
chenpf_at_njit.edu
In collaboration with D. Innes S. Solanki
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Researches on CMEs
Chen 2007, J. Astrophys. Astron.

• Pre-CME structures
• Initiation
• Propagation
• associated Phenomena
• Geo-effectiveness
• Forecast

How are CMEs triggered? How can CMEs be
predicted?
Precursors
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Precursors of CMEs
Chen, Innes, Solanki 2008, AA

1. Emerging Flux (Feynman Martin 1995)

(2) SXR brightenings (Harrison 1989)
(3) Radio Noise Storms
(4) Type III Radio Burst
(5) Filament Darkening Widening
Chen Shibata, 2000, ApJ., 545, 524
(6) Anymore?
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H? Observation from BBSO
2000 Sep 26 flare/CME event
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SUMER Spectral Observations
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Ocillating Motions
Amplitude 15 km/s Period 20 min
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Eruption
Lasco
EIT 195
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Synthesis of the event
Siphon flow ? pressure difference along a loop
Surge ? reconnection btw emerging flux corona
Prominence eruption flare ? CSHKP model
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Theoretical Explanation
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Filament Oscillation another precursor for CMEs?
Chen, Innes, Solanki, 2008, AA
Universality?
Tether-cutting model (Moore LaBonte 1980)
Ambiguity?
12 times the oscillation period in our case