All Figures

$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics{3354f1.eps}} \end{figure}$ Figure 1: Identification of analysed regions in NOAA8218. Upper left panel: EIT 195 Å image taken at 14:51 UT. The SVST field of view is overlaid Upper right panel: MDI continuum image taken at 14:50:34 UT. The SVST field of view is overlaid. Lower left panel: SVST H $\alpha$ corresponding field of view image taken at 14:57 UT. The overlaid box shows the area of Figs. 3 and 4. Lower right panel: SVST H $\alpha$ close up of area shown in Fig. 3. The overlaid box shows the area analysed in Fig. 5.
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In the text

$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics{3354f2.eps}} \end{figure}$ Figure 2: Figure showing the locations of the main features discussed in the text. The flaring region A, and non-flaring region B, are marked on both images. Left panel: G band image at 14:32:30 UT. The two sunspots are denoted X and Y. Thread-like structures between them and close to X are marked. Right panel: H $\alpha$ image at 14:34:00 UT. The inverted S-shaped feature is pointed out as are several arch filaments in region B. The approximate locations where the flare ribbons brighten are marked with LR and RR.
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In the text

$\begin{figure} \par\resizebox{20.5cm}{!}{\includegraphics{3354f3.eps}} \end{figure}$ Figure 3: 40.5 $\hbox {$^{\prime \prime }$ }$ by 42.2 $\hbox {$^{\prime \prime }$ }$ cutout of the observed FOV between 13:38 and 15:02 UT in the H $\alpha$ line centre and -700 mÅ blue wing. The blue wing images are denoted by H $\alpha$ - and the regions A and B are outlined. On the 13:38:04 UT image the arrows 1, 2 and 3 point out the filament structures before the flare. In the 14:57:34 UT image the arrows 1 and 2 point out the two structures which remain after the flare.
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In the text

$\begin{figure} \par\resizebox{20.5cm}{!}{\includegraphics{3354f4a.eps}} \end{figure}$ Figure 4: 40.5 $\hbox {$^{\prime \prime }$ }$ by 42.2 $\hbox {$^{\prime \prime }$ }$ cutout of the observed FOV between 12:48 and 16:22 UT. Magnetograms together with G-band and H $\alpha$ images are shown. Close to time coincident magnetograms are overlaid on some of the images and are labelled B/G and B/H $\alpha$ . The observation times are shown and the regions A and B are outlined.
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In the text

$\begin{figure} \par\resizebox{20.5cm}{!}{\includegraphics{3354f4b.eps}} \end{figure}$ Figure 4: continued.
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In the text

$\begin{figure} \par\resizebox{8cm}{!}{\includegraphics{3354f5.eps}} \end{figure}$ Figure 5: GOES-9 1 min X-ray flux light curves. The left y-axis is in flux units of Wm $^{-2} \times 10^{-7}$ . Light curves for the H $\alpha$ line center and -700 mÅ blue wing are also plotted with the right y-axis in arbitrary units. These are marked as H $\alpha$ and H $\alpha$ -, respectively. They are totals over a region of $\sim$ 23.7 by 22.0 arcsec shown by a box overplotted on the 14:52:55 UT image in the lower right hand panel of Fig. 1.
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In the text

$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics{3354f6.eps}} \end{figure}$ Figure 6: Time development of average magnetic flux and the percentage of saturated pixels for the flaring region (A in Fig. 4). Upper left - average Gauss (+ve). Lower left - average Gauss (-ve). Upper right - % of pixels saturated (+ve). Lower right - % of pixels saturated (-ve).
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In the text

$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics{3354f7.eps}} \end{figure}$ Figure 7: Time development of average magnetic flux and the percentage of saturated pixels for the non-flaring region (B in Fig. 4). Upper left - average Gauss (+ve). Lower left - average Gauss (-ve). Upper right - % of pixels saturated (+ve). Lower right - % of pixels saturated (-ve).
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In the text

$\begin{figure} \par\resizebox{6.5cm}{!}{\includegraphics{3354f8.eps}} \end{figure}$ Figure 8: Timeslice image showing the movement of RR towards LR (see text). The image on the lower left of the figure is taken from the G-band data at 12:49:33 UT and the magnetogram in the upper left was taken at 12:44:28 UT. Both are 42.2 by 42.2 arcsec in size. The slice-line is overlaid and the starting pixel (0) and ending pixel (148) are also shown. The absicca of the coordinate frame of the right hand plot shows the same pixel position along the slice-line. The ordinate shows the time.
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In the text

$\begin{figure} \par\resizebox{7.2cm}{!}{\includegraphics{3354f9.eps}} \end{figure}$ Figure 9: Timeslice image showing the separation of the structures in the non-flaring region, B. The G-band image and magnetogram are the same as before. The slice-line is overlaid and the starting pixel (0) and ending pixel (179) are also shown. The absicca of the coordinate frame of the right hand plot shows the same pixel position along the slice-line. The ordinate shows the time.
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In the text

$\begin{figure} \par\resizebox{5.7cm}{!}{\includegraphics{3354f10.eps}} \end{figure}$ Figure 10: Timeslice image showing emerging flux between LR and RR. The G-band image in this figure was taken at 13:35:52 UT and the magnetogram was taken at 13:36:20 UT. The slice-line is overlaid and the starting pixel (0) and ending pixel (112) are also shown. The absicca of the coordinate frame of the right hand plot shows the same pixel position along the slice-line. The ordinate shows the time.
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In the text

$\begin{figure} \par\resizebox{5cm}{!}{\includegraphics{3354f11.eps}} \end{figure}$ Figure 11: Timeslice image showing emerging flux between LR and RR. The G-band image in this figure was taken at 13:35:52 UT and the magnetogram was taken at 13:36:20 UT. The slice-line is overlaid and the starting pixel (0) and ending pixel (84) are also shown. The absicca of the coordinate frame of the right hand plot shows the same pixel position along the slice-line. The ordinate shows the time.
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In the text

$\begin{figure} \par\resizebox{7cm}{!}{\includegraphics{3354f12.eps}} \end{figure}$ Figure 12: Timeslice image showing the movement of the positive and negative polarity spots from SOHO/MDI data. The timeslice covers the SVST observations period and extends much later until around 05:00 UT on May 14th.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3354f13.eps} \end{figure}$ Figure 13: Results from the local correlation tracking method. The size of the area is the same as Figs. 3 and 4. The velocity map is plotted and the magnitude of the arrows are proportional to the distance travelled by the corresponding box although the absolute value is arbitrary (see text). The arrowhead gives the direction of motion. The underlying image image is the divergence map. White areas are regions of positive divergence and dark areas are regions of convergence. Contours of the G band dark spots are also overplotted with levels of 0.195% and 0.390%.
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In the text

$\begin{figure} \par\includegraphics[width=7cm,clip]{3354f14.eps} \end{figure}$ Figure 14: EIT 195 Å image of NOAA 8218 at the time of flare peak intensity (14:50:57 UT). corresponding to the SVST field of view as shown by the box on the EIT image in the upper left hand panel of Fig. 1. An MDI magnetogram has been overlaid to aid in cross identification of features with the SVST dataset. The magnetogram was taken at 14:58:05 UT. Positive polarity regions are denoted by dashed contours and negative polarity regions are denoted by solid contours.
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In the text

$\begin{figure} \par\includegraphics[width=6cm,clip]{3354f15.eps} \end{figure}$ Figure 15: SVST H $\alpha$ line center image taken just after the flare peak at 14:57:34 UT (closest in time to the EIT and MDI images of the previous figure). The EIT image has been overlaid as solid contours to show the locations of the brightenings. The contour surrounding LR is about 50% of the peak intensity of RR. A Yohkoh-SXT image taken at 14:56:06 UT is also overlaid as dashed contours. The percentages for the contour levels are the same in both overlays i.e. 20%, 50%, 80% and 100%.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{3354f16.eps} \end{figure}$ Figure 16: Schematic drawing of emerging twisted magnetic flux tube as discussed in the text.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3354f17.eps} \end{figure}$ Figure 17: Cartoon of emerging flux/coronal magnetic field reconnection. LR and RR correspond to the footpoints of the twisted structure shown in Fig. 12. Points A and B correspond to the footpoints of the overlying EIT loops. Partial reconnection occurs as shown in the figure The filled circle is located at the reconnection point. After reconnection some of the field lines rooted in A connect to RR and some of the field lines rooted in LR connect to B. The polarities noted from the MDI and SVST magnetograms are shown. The solid lines surrounding LR and RR/B correspond to the contour lines of the EIT brightenings (see Fig. 15). The dashed line represents the location of the SXT brightening. Note that the EIT peak intensity is situated closer to RR than LR (see text for discussion).
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In the text

$\begin{figure} \par {\hspace*{6mm}\includegraphics[width=7.5cm,clip]{3354f18a.ep... ... \par\vspace*{5mm} \includegraphics[width=8.8cm,clip]{3354f18b.eps} \end{figure}$ Figure 18: Evidence for brightenings at the coronal loop footpoints. Upper panel: EIT 195 Å image taken at 14:51 UT. Area 1 is around the flare region and Area 2 is around the other footpoint of the coronal loop. The dotted region marks the control area with the most significant brightening (see text). Lower panel: Time profiles of the intensities in Areas 1 and 2.
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In the text

$\begin{figure} \par\resizebox{20.5cm}{!}{\includegraphics{3354f4a.eps}} \end{figure}$	Figure 4: 40.5 $\hbox {$^{\prime \prime }$ }$ by 42.2 $\hbox {$^{\prime \prime }$ }$ cutout of the observed FOV between 12:48 and 16:22 UT. Magnetograms together with G-band and H $\alpha$ images are shown. Close to time coincident magnetograms are overlaid on some of the images and are labelled B/G and B/H $\alpha$ . The observation times are shown and the regions A and B are outlined.
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$\begin{figure} \par\resizebox{20.5cm}{!}{\includegraphics{3354f4b.eps}} \end{figure}$	Figure 4: continued.
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$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics{3354f6.eps}} \end{figure}$	Figure 6: Time development of average magnetic flux and the percentage of saturated pixels for the flaring region (A in Fig. 4). Upper left - average Gauss (+ve). Lower left - average Gauss (-ve). Upper right - % of pixels saturated (+ve). Lower right - % of pixels saturated (-ve).
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$\begin{figure} \par\resizebox{8.8cm}{!}{\includegraphics{3354f7.eps}} \end{figure}$	Figure 7: Time development of average magnetic flux and the percentage of saturated pixels for the non-flaring region (B in Fig. 4). Upper left - average Gauss (+ve). Lower left - average Gauss (-ve). Upper right - % of pixels saturated (+ve). Lower right - % of pixels saturated (-ve).
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$\begin{figure} \par\resizebox{7.2cm}{!}{\includegraphics{3354f9.eps}} \end{figure}$	Figure 9: Timeslice image showing the separation of the structures in the non-flaring region, B. The G-band image and magnetogram are the same as before. The slice-line is overlaid and the starting pixel (0) and ending pixel (179) are also shown. The absicca of the coordinate frame of the right hand plot shows the same pixel position along the slice-line. The ordinate shows the time.
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$\begin{figure} \par\resizebox{7cm}{!}{\includegraphics{3354f12.eps}} \end{figure}$	Figure 12: Timeslice image showing the movement of the positive and negative polarity spots from SOHO/MDI data. The timeslice covers the SVST observations period and extends much later until around 05:00 UT on May 14th.
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$\begin{figure} \par\includegraphics[width=8cm,clip]{3354f16.eps} \end{figure}$	Figure 16: Schematic drawing of emerging twisted magnetic flux tube as discussed in the text.
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$\begin{figure} \par {\hspace{6mm}\includegraphics[width=7.5cm,clip]{3354f18a.ep... ... \par\vspace{5mm} \includegraphics[width=8.8cm,clip]{3354f18b.eps} \end{figure}$	Figure 18: Evidence for brightenings at the coronal loop footpoints. Upper panel: EIT 195 Å image taken at 14:51 UT. Area 1 is around the flare region and Area 2 is around the other footpoint of the coronal loop. The dotted region marks the control area with the most significant brightening (see text). Lower panel: Time profiles of the intensities in Areas 1 and 2.
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