Abstract:
The evolution of an X2.7 solar flare, that occurred in a complex βγ δ magnetic
configuration region on 3 November 2003 is discussed by utilizing a multi-wavelength data
set. The very first signature of pre-flare coronal activity is observed in radio wavelengths
as a type III burst that occurred several minutes prior to the flare signature in Hα. This
type III burst is followed by the appearance of a loop-top source in hard X-ray (HXR)
images obtained from RHESSI. During the main phase of the event, Hα images observed
from ARIES solar tower telescope, Nainital, reveal well-defined footpoint (FP) and loop-top
(LT) sources. As the flare evolves, the LT source moves upward and the separation between
the two FP sources increases. The co-alignment of Hα with HXR images shows spatial
correlation between Hα and HXR footpoints, whereas the rising LT source in HXR is always
located above the LT source seen in Hα. The evolution of LT and FP sources is consistent
with the reconnection models of solar flares. The EUV images at 195 Å taken by SOHO/EIT
reveal intense emission on the disk at the flaring region during the impulsive phase. Further,
slow-drifting type IV bursts, observed at low coronal heights at two time intervals along the
flare period, indicate rising plasmoids or loop systems. The intense type II radio burst at a
time in between these type IV bursts, but at a relatively greater height, indicates the onset
of CME and its associated coronal shock wave. The study supports the standard CSHKP
model of flares, which is consistent with nearly all eruptive flare models. More importantly,
the results also contain evidence for breakout reconnection before the flare phase.
