Solar Erupting Filaments and Magnetic Field Configurations of IP Magnetic Clouds Yuming Wang 1, 2 & Jie Zhang 1 (Presenting) 1 George Mason University 2 University of Science & Technology of China Paper by Wang, et al., ApJ, 651, 2006 GMU

It is generally believed that the axial orientation of MCs is parallel to the long axis of filaments. [e.g., Bothmer and Schwenn 1994; Bothmer and Rust 1997; Marubashi 1997; McAllister et al. 2001; Yurchyshyn et al. 2001; Jing et al. 2004; Rust et al ] EW N S + ¯ Sun Flux rope

Here, we further take the curvature of filament axis into account, when compared with MC axis Three filament-MC events are analyzed. The selection of filaments satisfies the following criteria:  The filament and its orientation is well observed in Halpha images, i.e., large and dark enough  There is no complex filament system in the source region.

August 9, 2000 event

~2.5 days later

October 9, 2000 event

~3.5 days later

November 18, 2003 event

~2 days later

70~90° 47° Consistent with the central part of the filament Inconsistent Leading front

Why is the axis of MCs not consistent with that of filaments for some events?  A CME is a large scale phenomenon, in which filament itself (seen in Halpha) is only a small part of the eruptive magnetic structure [e.g., Harrison & Lyons 2000; Plunkett et al. 2001].  A MC is also a large scale structure. The in-situ observation only see a line through the 3-D MC.  A CME may rotate when it moves outward [e.g., Fan & Gibson 2004; Torok & Kliem 2005].  Error in fitting the observations of magnetic clouds When the filament is curved, what portion correspond to the axis of MC?