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Physics of Solar Prominences: II—Magnetic Structure and Dynamics

“…To determine the directions of the axial fields in the three filament segments, Schmieder et al (2004) used the chirality rules for chromospheric fibrils and magnetic field polarity, the skew of the overlying coronal arcades, and the sense of twist in neighboring sunspots. It was then confirmed that when two filaments interact, magnetic reconnection takes place and leads to a merging when their chiralities are of the same sign, but leads to a flare when the chiralities are opposite (also see Malherbe, 1989;Martin, 1998;Rust, 2001;van Ballegooijen, 2004;DeVore et al, 2005). It was also inferred that magnetic helicity must slowly accumulate prior to filament merging, as seen by the rotation of a small twisted sunspot close to the merging point.…”

“…The barbs, as well as the ends of the filament (also called "legs") may be a collection of threads that appear to terminate at a single point or at multiple points (Lin et al, 2008a). When viewing a quiescent filament on the solar disk at high resolution, Hα observations indicate that each of these three structural components consist of thin thread-like structures (see examples in Malherbe, 1989;Martin, 1998;Pecseli and Engvold, 2000). In Figure 2 these thin threads may be seen, where the observations are at the limit of present day resolution.…”

“…5. Barbs -lateral extensions from the prominence spine toward patches of parasitic polarity with vertical extents much greater than the local gravitational scale height -apparently are connected to the chromosphere (Kiepenheuer, 1953;Malherbe, 1989;Martin, 1998;.…”

“…10) generally invoke reconnection low in the solar atmosphere as the pivotal cause of mass at prominence temperatures being expelled into the corona (Wang, 1999;). This conjecture is largely motivated by the well-observed, but poorly understood, connection between flux cancellation and filament channel formation (van Ballegooijen and Martens, 1989;Martin, 1998;Wang and Muglach, 2007). Because injection necessarily produces unidirectional flows in each flux tube, counterstreaming could arise either through reconnection occurring at the bases of different flux tubes on opposite sides of the PIL or through sequential reconnection at each footpoint.…”

Probability of Solar Flares Turn out to Form a Coronal Mass Ejections Events due to the Characterization of Solar Radio Burst Type II and III

“…This is because a region of strong magnetic nonpotentiality narrowly collimated around a Polarity Inversion Line (PIL) plays the critical role here, but the exact topology remains controversial [98,99]. It should be noted that the role of CMEs in flare energetics is complicated.…”