Solar Erupting Filaments and Magnetic Field Configurations

of IP Magnetic Clouds

Yuming Wang1, 2 & Jie Zhang1 (Presenting)1George Mason University

2University of Science & Technology of China

Paper by Wang, et al., ApJ, 651, 2006

GMU 10-2006

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. 2005.]

E W

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?