SOHO/SUMER Observations of Prominence Oscillation before Eruption

Department of Astronomy

Nanjing University

Nanjing 210093

China

chenpf@nju.edu.cn

chenpf@njit.edu

P. F. Chen

In collaboration with

D. Innes & S. Solanki

Researches on CMEs

1. Pre-CME structures

2. Initiation

3. Propagation

+ associated Phenomena

4. Geo-effectiveness

5. Forecast

PrecursorsHow are CMEs triggered?

How can CMEs be predicted?

Chen 2007, J. Astrophys. & Astron.

Precursors of CMEs

(1) Emerging Flux (Feynman & Martin 1995)

Chen, Innes, & Solanki 2008, A&A

Chen & Shibata, 2000, ApJ., 545, 524

(2) SXR brightenings (Harrison 1989)

(3) Radio Noise Storms

(4) Type III Radio Burst

(5) Filament Darkening & Widening

(6) Anymore?

H Observation from BBSO

2000 Sep 26 flare/CME event

SUMER Spectral Observations

Ocillating Motions

Amplitude: ~15 km/s

Period: ~20 min

Eruption

EIT 195 Lasco

Synthesis of the event

Surge reconnection btw emerging flux & corona

Siphon flow pressure difference along a loop

Prominence eruption & flare CSHKP model

Theoretical Explanation

Filament Oscillation— another precursor for CMEs?

Ambiguity?

Tether-cutting model (Moore &LaBonte 1980)

Universality?

12 times the oscillation period in our case

Chen, Innes, & Solanki, 2008, A&A