A&A 479, 859-864 (2008)
Large-scale disturbances preceding a fast halo CMEW.-G. Zong
National Center for Space Weather, China Meteorological Administration, Beijing 100081, PR China
(Received 30 August 2007 / Accepted 10 December 2007)
Aims.The nature of coronal waves, often termed "EIT waves" is still unclear. Therefore new efforts are needed to investigate large-scale disturbances during solar eruptions. In this paper, we present observations of an event occurring on 19 January 2005, and study the large-scale disturbance during the event in detail.
Methods.Using the high cadence images from SXI onboard GOES-12, the large-scale disturbance is identified. Combined with EIT 195 Å images, TRACE UV 1600 Å images, RHESSI hard X-ray data and MDI/SOHO longitudinal magnetic field maps, the intrinsic process of the large-scale disturbance is discussed.
Results.The large-scale disturbance propagated over a distance about 3.8105 km at a velocity of about 390 km s-1. Along the trajectory of the disturbance, a brightening line was left behind, which was coincident with the dense structure in EIT intensity images. With the morphology and metric radio spectrum data, it was found that the disturbance was not a wave but the low-coronal signatures of the eruption.
Key words: Sun: flares -- Sun: coronal mass ejections (CMEs) -- Sun: magnetic fields
© ESO 2008