Astronomy & Astrophysics

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$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig1.ps} \end{figure}$ Figure 1: Continuum ( top) and line-of-sight velocity map ( bottom) of NOAA 9451. The velocity map was obtained by a two component inversion, only the component with the larger filling factor is shown. The black contour lines give the values for the magnetic field strength in Gauss as derived from the inversion of the He I profiles. The green box marks "region 1'' which is used for further analysis, the black diamond the location of the profile plotted in Fig. 4. The magenta contour line indicates the region where the separation of the two components in wavelength was large enough to allow for the retrieval of two magnetically independent components. To increase the contrast the velocity map saturates at 15 km s^-1 (the highest velocity values in the yellow region are 40 km s^-1). Black lines indicate projections of samples of reconstructed magnetic loops (see Wiegelmann et al. 2005; Solanki et al. 2003).
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In the text

$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig2.eps} \end{figure}$ Figure 2: Photospheric line-of-sight velocity map for the same region as shown in Fig. 1, retrieved from the Si I 1082.7 nm line. The contour lines refer to the chromospheric magnetic field strength as derived from the He I inversions. Note the different velocity scale compared to Fig. 1.
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In the text

$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig3.eps} \end{figure}$ Figure 3: Stokes I profile along a reconstructed magnetic loop from the loop apex ( top profile) to the footpoint ( bottom profile). Close to the footpoints the supersonic downflow component becomes clearly visible. The vertical, dashed lines show the nominal wavelengths of the three components of the He I triplet (transitions Tr1, Tr2 and Tr3). The numbers above each profile indicate the x and y position in Fig. 1 (in Mm).
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In the text

$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig4.eps} \end{figure}$ Figure 4: Stokes profiles showing two distinct magnetic components for the pixel indicated by the black diamond in Fig. 1. The observed profiles are shown in black, the fits in red (two independent magnetic components, $B_{\rm slow}=725~\mbox{G}$ , $\gamma _{\rm slow}=30^\circ {}$ and $B_{\rm fast}=1194~\mbox{G}$ , $\gamma _{\rm fast}=68^\circ {}$ , fitness f=2.10) and green (2 magnetic components with coupled magnetic field $B_{\rm slow}=B_{\rm fast}=642~\mbox{G}$ , $\gamma _{\rm slow}=\gamma _{\rm fast}=61^\circ {}$ , fitness f=1.71). The two components are shifted by 28 km s^-1 relative to each other. The orange line shows a fit assuming one broad absorbing component superposed with a central emission component (fitness f=1.50). The fit involving two independent magnetic components best reproduces the observed Stokes vector. The dashed, blue line indicates the weighting scheme used for the inversion, the vertical, dotted lines show the central wavelengths of the three components of the He I triplet.
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In the text

$\begin{figure}\par \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig5a.ps} \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig5b.ps} \end{figure}$ Figure 5: Temporal variation of LOS-velocity in the region of maximum downflow, for the fast component ( top) and the slow component ( bottom). The presented area corresponds to the area within the green rectangle in Fig. 1 ("region 1'', size $3 \times 3$ Mm²). The observations span an interval of 73 min. The fast component of a 2-component model is plotted only if the filling factor is larger than 0.20. The area where the He I-line goes into emission is marked in gray. The magenta contour line encloses the region where the separation and filling factor of both components allow for the retrieval of the magnetic field vector separately for both components. Note the difference in velocity scale for the two components.
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In the text

$\begin{figure}\par \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig6a.ps} \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig6b.ps} \end{figure}$ Figure 6: Same as Fig. 5 but for inclination angle of fast ( top) and slow component ( bottom) in the solar reference frame. The same color scale is used for both components.
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In the text

$\begin{figure}\par \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig7a.ps} \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig7b.ps} \end{figure}$ Figure 7: Same as Fig. 5 but for the magnetic field strength of fast ( top) and slow component ( bottom). The same color scale is used for both components.
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In the text

$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig8.eps} \end{figure}$ Figure 8: Typical emission profile (Stokes I and V only), taken from gray shaded area in Fig. 5. The emission signal is redshifted by $\approx$ 10 km s^-1. The red line shows the best fit profile assuming one absorbing component and an independent emitting component.
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In the text

$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig9.eps} \end{figure}$ Figure 9: Sketch of the possible magnetic field topologies at a loop footpoint. a) The "uncombed model'' is indicated by the different inclination angle between the flux-tube field lines (yellow) and the surrounding field lines (red) in the upper chromosphere. b) In the "cloud model'' the two different velocity components originate from different heights, the fast downflow component lying above the slow component. The photospheric field obtained from the inversion of the Si I line is indicated by the green arrows. The inclination angles of the arrows represent the measured magnetic field direction. The emission region, possibly caused by a shock, is indicated by the yellow area. Note that the height information is not to scale.
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In the text

$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig2.eps} \end{figure}$	Figure 2: Photospheric line-of-sight velocity map for the same region as shown in Fig. 1, retrieved from the Si I 1082.7 nm line. The contour lines refer to the chromospheric magnetic field strength as derived from the He I inversions. Note the different velocity scale compared to Fig. 1.
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$\begin{figure}\par \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig6a.ps} \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig6b.ps} \end{figure}$	Figure 6: Same as Fig. 5 but for inclination angle of fast ( top) and slow component ( bottom) in the solar reference frame. The same color scale is used for both components.
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$\begin{figure}\par \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig7a.ps} \includegraphics[height=8.8cm,clip=TRUE,angle=90]{4700fig7b.ps} \end{figure}$	Figure 7: Same as Fig. 5 but for the magnetic field strength of fast ( top) and slow component ( bottom). The same color scale is used for both components.
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$\begin{figure}\par \includegraphics[width=8.8cm,clip=TRUE]{4700fig8.eps} \end{figure}$	Figure 8: Typical emission profile (Stokes I and V only), taken from gray shaded area in Fig. 5. The emission signal is redshifted by $\approx$ 10 km s^-1. The red line shows the best fit profile assuming one absorbing component and an independent emitting component.
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