Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=11.8cm,clip]{Hf202_f1.eps}\end{figure}$ Figure 1: QPP on February 5-6 2003. a), b) Full disk measurements in X-rays from GOES-8 (1-8 Å and 0.5-4 Å) and RHESSI (3-6 keV, 6-12 keV and 12-25 keV). The vertical dashed lines indicate the peak times of the flares, as seen by GOES 1-8 Å. c), d) RHESSI averaged flux and SXI intensity in region A (black) and B (grey). RHESSI curves, shown as solid lines, are averaged flux above 80% of the maximum value in 5-12 keV RHESSI images reconstructed from collimators 1F and 3F-6F. The SXI curves are shown as dot-dashed lines in the Open filter (6-80 Å with short integration time of 0.0155 s) and as dashed lines in the Thin Polyimide filter (6-60 Å with integration time of 0.3345 s; scales are arbitrary). e), f) Fits, shown as solid thick lines, for the detrended curves $J/J_{\rm o}$ , where e) J² is the GOES 0.5-4 Å curve and $J_{\rm o}$ is a linear trend; f) J² is the RHESSI 6-12 keV curve and $J_{\rm o}$ is the residual in a wavelet à trous decomposition (Starck & Murtagh 2002). This latter method decomposes a time series in a sequence of approximations of the signal that have increasing time scales. The trend $J_{\rm o}$ obtained was found to be more appropriate than a linear trend for the type of time series studied, and is smoother than a running average.
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In the text

$\begin{figure} \par\includegraphics[width=5.2cm,clip]{Hf202_f2.eps}\end{figure}$ Figure 2: Difference of EIT 195 Å images taken on February 2003, at 21:36 UT on the 5th and 02:12 UT on the 6th. The two principal active sources are denoted "A'' and "B'' and the transequatorial loop, shown between dashed lines, ``TL''. The contrast in the off-disk area is enhanced using histogram-equalisation.
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In the text

$\begin{figure} \par\includegraphics[width=11.8cm,clip]{Hf202_f3.eps}\end{figure}$ Figure 3: a), b) EIT 195 Å images of region B and c), d) H $\alpha$ images of region A at the time of the first and second sequence of QPP. Superimposed are the contour levels of: 5-12 keV RHESSI images (reconstructed from collimators 1F and 3F-6F) shown in solid lines (at 50 and 80% of the maximum value), the longitudinal magnetic field observed by MDI in thin lines (solid for positive field and dashed for negative field), H $\alpha$ images in thick black (80 and 90%, in a) and b)) and EIT 195 Å images in thick solid lines (50 and 80%, in c) and d)). a), c) Images taken on 5 February 2003 are co-aligned at 21:52:18 UT. This includes an H $\alpha$ image from BBSO (21:43:57 UT), images by EIT (21:47:32 UT), MDI (20:53 UT, with contour levels multiple of $2 \times 10^{-2}$ Tesla-equivalent) and a RHESSI image (in the time range 21:51:47-21:52:49 UT, shown in a)). b), d) Images taken on 6 February 2003 are co-aligned at 2:20:54 UT. This includes H $\alpha$ images from Learmonth (2:27:44 UT in b), 2:16:39 UT in d)), images by EIT (2:22:48 UT), MDI (3:17 UT, with contour levels multiple of 10^-2 Tesla-equivalent), and RHESSI images (in the time range 02:17:19-02:18:20 UT in b) and 2:20:23-2:21:24 UT in d)).
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In the text

$\begin{figure} \par\includegraphics[width=5.2cm,clip]{Hf202_f2.eps}\end{figure}$	Figure 2: Difference of EIT 195 Å images taken on February 2003, at 21:36 UT on the 5th and 02:12 UT on the 6th. The two principal active sources are denoted "A'' and "B'' and the transequatorial loop, shown between dashed lines, ``TL''. The contrast in the off-disk area is enhanced using histogram-equalisation.
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