Heliophysics Events Knowledgebase Coverage Registry (HCR)
Observation Details
XRT: HOP35 AR Tracking
2007-12-08T18:24:54 to 2007-12-09T00:09:54
Science Goal: DST/IBIS, Hinode/EIS+SOT+XRT, SOHO/MDI and TRACE -Magnetic helicity in active filaments
Program: HOP35_AR_Tracking_3
Target: AR
xcen=0 ycen=0
Instrument: XRT
HOP/JOP: 0
Description: Daily Note: SOT: - HOP 35 XRT: - HOP 35 - support EIS coronal hole studies. Co-alignment program: (** This Alignment program is CANCELED this weekend, due to solar activity prospects.) - Run standard co-alignment program: 2 hr for N 945 arcsec, 2hr for E -945 arcsec - In addition, run the co-alignment program: 30 min for S -945 arcsec and another 30 min for W 945 arcsec to check the mis-alignment between SOT and AOCS. EIS: TBD
Request to XRT HOP Number 0035:
Other Instruments: DST/IBIS SoHO/MDI TRACE
Scientific Objectives: We want to investigate whether the conditions for filament eruption occurrence depends on the shear / twist of the filament magnetic field or on the interaction between the highly sheared core field of the filament and the overlying flux rope. In this context, two main theoretical models have been proposed. The former suggests that the magnetic eruption and the impulsive energy release begins deep in the highly sheared core field of the filament and the overlying flux rope then erupts into interplanetary space (Moore et al., 2001). The latter assumes that a sheared core field pushes through an overlaying restraining filed and that a slow reconnection begins at a neutral point high in corona. After the restraining force of the overlaying field significantly weakens because of the reconnection, the sheared core field explosively erupts into interplanetary space (Antiochos, 1998). We think that the measure of the magnetic helicity or of its flux from the photosphere into the filament axis and the study of the magnetic topology of the active region where the filament eruption occurs, will give us the opportunity to discriminate between these two theoretical models.

Annotations:
Hits: 33
Chief Observer
SHIN, Junho and McKENZIE, David and Savage, S.
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