On Magnetic Flux Budget in Low-corona Magnetic Reconnection and Interplanetary Coronal Mass Ejections
Jiong Qiu Submitted: 2006-11-03 15:39
We present the first quantitative comparison between the
total magnetic reconnection flux in the low-corona in the wake of
coronal mass ejections (CMEs) and the magnetic flux in
magnetic clouds (MCs) that reach 1 AU 2 - 3 days after CME onset.
The total reconnection flux is measured from flare ribbons, and the MC flux
is computed using in-situ observations at 1 AU, all ranging from 1020-22 Mx.
It is found that for the studied 9 events in which the association between flares, CMEs, and MCs is
identified, the MC flux is correlated with the total reconnection flux Phi_r. Further, the
poloidal (azimuthal) MC flux Phi_p is comparable with reconnection flux Phir,
and the toroidal (axial) MC flux Phi_t is a fraction of Phir. Events associated with filament eruption
do not exhibit a different Phit, p - Phi_r relation from events not accompanied by erupting filaments.
The revealed relations between these independently measured physical quantities suggest that,
for the studied samples, the magnetic flux and twist of interplanetary magnetic flux ropes, reflected by MCs,
are highly relevant to low-corona magnetic reconnection during the eruption.
%which contributes significantly to the formation of the helical structure of the flux ropes.
We discuss the implication on the formation mechanism of twisted magnetic flux ropes, namely,
whether the helical structure of the magnetic flux rope is largely pre-existing or
formed in-situ by low-corona magnetic reconnection. We also measure magnetic flux
encompassed in coronal dimming regions (Phi_d) and discuss its relation with reconnection
flux inferred from flare ribbons and MC flux.
Authors: Jiong Qiu, Qiang Hu, Timothy, A. Howard, Vasyl, B. Yurchyshyn
Publication Status: ApJ (accepted)
Last Modified: 2006-12-19 14:55