Multi-scale reconenctions in a complex CME

VAN DRIEL-GESZTELYI, L.; GOFF, C.P.; DÉMOULIN, P.; CULHANE, J.L.; MATTHEWS, S.A.; HARRA, L.K.; MANDRINI, C.H.; KLEIN, K.-L.; KUROKAWA, H.

ADVANCES IN SPACE RESEARCH

Elsevier

Año: 2008 vol. 42 p. 858 - 865

0273-1177

A series of flares GOES class M M and C and a CME were observed on 20-JAN-2004 occurring in close succession in NOAA 10540 Types II III and an N radio bursts were associated We use the combined observations from TRACE EIT H-alpha images from Kwasan Observatory MDI magnetograms GOES and radio observations from Culgoora and Wind WAVES to understand the complex development of this event We link the first two impulsive flares to tether-cutting reconnections and the launch of the CME while the last of the flares an LDE to the relaxation phase following forced reconnections between the erupting flux rope and neighbouring magnetic field lines We show that reconnection with the magnetic structure of a previous CME launched about 8 hours earlier injects electrons into open field lines having a local dip and apex of about 6 solar radii height The dipped shape of these field lines was due to large-scale magnetic reconnection between expanding magnetic loops and open field lines of a neighbouring streamer This particular situation explains the observed decametric N burst and why N-bursts are so rare.