Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg01.eps} \end{figure}$ Figure 1: Data from August 4, 2003, NOAA 10425, $\mu =0.76$ . Left: reference image, right: magnetogram. DC - Disk center, N - solar north. The ellipse plotted in the reference image shows the projection of a circle at a LOS angle of 39 $\hbox {$^\circ $ }$ . Minor tickmarks are $1\hbox {$^{\prime \prime }$ }$ apart.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg02.eps} \end{figure}$ Figure 2: Data from August 8, 2003, NOAA 10425, $\mu =0.96$ . Left: reference image, right: magnetogram. DC - Disk center, N - solar north. The ellipse plotted in the reference image shows the projection of a circle at a LOS angle of 16 $\hbox {$^\circ $ }$ . Minor tickmarks are $1\hbox {$^{\prime \prime }$ }$ apart.
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In the text

$\begin{figure} \par\includegraphics[width=14.1cm,clip]{2678fg03.eps} \end{figure}$ Figure 3: Data from August 9, 2003, NOAA 10425, $\mu =0.88$ . a) Reference image; b) Dopplergram, range -3000 m s^-1 to 3000 m s^-1; c) corrector map, range 0.6 to 1.3; d) corrected magnetogram. DC - Disk center, N - solar north. The ellipse plotted in the reference image shows the projection of a circle at a LOS angle of 28 $\hbox {$^\circ $ }$ . Minor tickmarks are $1\hbox {$^{\prime \prime }$ }$ apart.
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In the text

$\begin{figure} \par\includegraphics[width=14.1cm,clip]{2678fg04.eps} \end{figure}$ Figure 4: Data from Jul. 2, 2003, NOAA 10397, $\mu =0.97$ . Left: reference image, right: magnetogram. DC - Disk center, N - solar north. The ellipse plotted in the reference image show the projection of a circle at a LOS angle of 12 $\hbox {$^\circ $ }$ . Minor tickmarks are $2\hbox {$^{\prime \prime }$ }$ apart. This spot has opposite polarity to that of NOAA 10425. For clarity the magnetogram signal is inverted for the analysis.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg05.eps} \end{figure}$ Figure 5: Left: line scan of Fe I 630.2 nm. The solid curve is the measured line profile (interpolated) and the dashed dotted curve is the atlas profile convolved with a simple transmission profile with FWHM value corresponding to that of the SOUP filter. The two vertical lines correspond to the nominal (for zero Doppler shift) wavelengths of the recorded magnetograms in the blue and red wings (line center position $\pm 5$ pm). Right: velocity calibration for the measured line profile (solid) - used to define the calibration function $f_{\rm c}$ - and the convolved atlas profile (dashed-dotted).
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In the text

$\begin{figure} \par\includegraphics[width=6.1cm,clip]{2678fg06.eps}\end{figure}$ Figure 6: Field geometry. The azimuth angle $\varphi$ is defined such that $\varphi =90\hbox {$^\circ $ }$ points to disk center. The angle of inclination $\gamma$ and the heliocentric angle $\vartheta$ are measured relative to the normal of the solar surface.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg07.eps} \end{figure}$ Figure 7: Influence of a velocity field on the magnetogram signal. Line indication as in Fig. 5. Left: stokes V/I (solid) and Stokes I (dashed-dotted, scale to the right) averaged over the penumbra of NOAA 10425 (August 9), obtained with the Polarimetric Littrow Spectrograph at the German Vacuum Tower Telescope on Tenerife. Right: variation in magnetogram signal vs. LOS velocity. Black and gray curves refer to measurements in the blue and red wings of the Fe I 630.2 nm line, respectively.
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In the text

$\begin{figure} \par\includegraphics[width=7.5cm]{2678fg08.eps} \end{figure}$ Figure 8: Temperature dependence of the magnetogram signal. The Stokes V/I signal is normalized to the value of Stokes V/I that corresponds to the mean penumbral temperature stratification of del Toro Iniesta et al. (1994) ( $\Delta T=0)$ .
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{2678fg09.eps} \end{figure}$ Figure 9: Separation of dark and bright filaments based on the broadband continuum data. a) Spot segment where a ring of constant distance from spot center is high-lightened. The black solid line indicates the boundary of the penumbra toward the granulation, the white line the boundary toward the umbra. b) The solid curve illustrates the azimuthal intensity variation along the ring, including all data points. The dashed curve denotes the locally defined cut-off-intensity. The data points that belong to the bright components are marked by open circles, the data points that belong to the dark components by solid circles. c) Illustration of the validity of magnetogram-signal-related masks. CS - center-side, LS - limb-side. See text for discussion.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{2678fg10.eps} \end{figure}$ Figure 10: Top: center-side penumbra (REF, MB) of the symmetric sunspot (NOAA 10425, LOS angle 16 $\hbox {$^\circ $ }$ , August 4), Bottom: center-side penumbra (REF, MB) of the large less symmetric sunspot (NOAA 10397, LOS angle 12 $\hbox {$^\circ $ }$ , July 2). (The large less symmetric sunspot has opposite polarity to that of NOAA 10425.) Distance between minor tickmarks corresponds to $0\hbox{$.\!\!^{\prime\prime}$ }5$ .
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{2678fg11.eps} \end{figure}$ Figure 11: Evolution of dark-cored filaments during 1h 35min in the G continuum ( top) and magnetogram ( bottom). One tickmark corresponds to $1\hbox {$^{\prime \prime }$ }$ .
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{2678fg12.eps}\end{figure}$ Figure 12: Azimuthal slices for NOAA 10425 on August 4, 2003 ( $\mu =0.76$ ) and August 9, 2003 ( $\mu =0.88$ ): inner penumbra r=0.45, mid penumbra r=0.70 and outer penumbra r=0.95. Gray and black dots refer to the bright and dark component, respectively, as selected by the continuum intensity mask. The sinusoidals, denoted by gray curves, show the fits which take only the data points of the dark components into account. The black sinusoidals refer to the bright components and the dashed sinusoidal is based on all data points. The horizontal lines, representing the vertical LOS component, are indicated in the same way.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg13.eps} \end{figure}$ Figure 13: Average radial variation of the magnetic field magnitudes based on all data sets of the symmetric sunspot, NOAA 10425, observed on August 4, 8 and 9. a) Continuum intensity, normalized to quiet sun intensity; b) horizontal component of the magnetogram signal (arbitrary units); c) vertical component of the magnetogram signal; d) inclination of the magnetic field; e) absolute strength of the magnetogram signal; f) vector plot of magnetic field from the data of d) and e). Black arrows represent the penumbral component B as selected by the magnetogram-based mask, gray arrows component A. Vertical dashed lines show the limits of umbra and penumbra. The symbols in the diagrams a)-e) refer to data points selected by the different types of mask as described in Sect. 3.6 and indicated in the lower right. The pluses correspond to selecting all data points at a given radius.
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In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{2678fg14.eps} \end{figure}$ Figure 14: Single measurement of magnetic field inclination of the small circular sunspot (Aug. 4, UT 14:25). Dark symbols refer to the calculation of $\gamma$ based on a magnetogram that is corrected for the influence of the flow field, the gray symbols in the background to the calculation based on the uncorrected magnetogram (cf. Sect. 3.3).
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In the text

$\begin{figure} \par\includegraphics[width=8.7cm,clip]{2678fg15.eps} \end{figure}$ Figure 15: Results for NOAA 10397. Inclination of the magnetic field, based on data observed on July 1, 2 and 5. Continuum intensity related data only based on July 2 and 5.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg16.eps} \end{figure}$ Figure 16: Correlation diagrams: magnetic field vs. inclination angle. (Diagrams based on NOAA 10425 data.) Left: high-signal components, right: low-signal components. Symbols as in Fig. 13.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg17.eps} \end{figure}$ Figure 17: Comparison of the flow field and magnetic field inclination of the symmetric sunspot, NOAA 10425, August 9, 2003. a) Inclination angle of the flow field; b) inclination angle of the magnetic field. Vertical dashed lines show the limits of umbra and penumbra. Symbols are explained in Fig. 13.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg01.eps} \end{figure}$	Figure 1: Data from August 4, 2003, NOAA 10425, $\mu =0.76$ . Left: reference image, right: magnetogram. DC - Disk center, N - solar north. The ellipse plotted in the reference image shows the projection of a circle at a LOS angle of 39 $\hbox {$^\circ $ }$ . Minor tickmarks are $1\hbox {$^{\prime \prime }$ }$ apart.
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$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg02.eps} \end{figure}$	Figure 2: Data from August 8, 2003, NOAA 10425, $\mu =0.96$ . Left: reference image, right: magnetogram. DC - Disk center, N - solar north. The ellipse plotted in the reference image shows the projection of a circle at a LOS angle of 16 $\hbox {$^\circ $ }$ . Minor tickmarks are $1\hbox {$^{\prime \prime }$ }$ apart.
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$\begin{figure} \par\includegraphics[width=6.1cm,clip]{2678fg06.eps}\end{figure}$	Figure 6: Field geometry. The azimuth angle $\varphi$ is defined such that $\varphi =90\hbox {$^\circ $ }$ points to disk center. The angle of inclination $\gamma$ and the heliocentric angle $\vartheta$ are measured relative to the normal of the solar surface.
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$\begin{figure} \par\includegraphics[width=7.5cm]{2678fg08.eps} \end{figure}$	Figure 8: Temperature dependence of the magnetogram signal. The Stokes V/I signal is normalized to the value of Stokes V/I that corresponds to the mean penumbral temperature stratification of del Toro Iniesta et al. (1994) ( $\Delta T=0)$ .
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{2678fg11.eps} \end{figure}$	Figure 11: Evolution of dark-cored filaments during 1h 35min in the G continuum ( top) and magnetogram ( bottom). One tickmark corresponds to $1\hbox {$^{\prime \prime }$ }$ .
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$\begin{figure} \par\includegraphics[width=8.6cm,clip]{2678fg14.eps} \end{figure}$	Figure 14: Single measurement of magnetic field inclination of the small circular sunspot (Aug. 4, UT 14:25). Dark symbols refer to the calculation of $\gamma$ based on a magnetogram that is corrected for the influence of the flow field, the gray symbols in the background to the calculation based on the uncorrected magnetogram (cf. Sect. 3.3).
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$\begin{figure} \par\includegraphics[width=8.7cm,clip]{2678fg15.eps} \end{figure}$	Figure 15: Results for NOAA 10397. Inclination of the magnetic field, based on data observed on July 1, 2 and 5. Continuum intensity related data only based on July 2 and 5.
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$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg16.eps} \end{figure}$	Figure 16: Correlation diagrams: magnetic field vs. inclination angle. (Diagrams based on NOAA 10425 data.) Left: high-signal components, right: low-signal components. Symbols as in Fig. 13.
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$\begin{figure} \par\includegraphics[width=14cm,clip]{2678fg17.eps} \end{figure}$	Figure 17: Comparison of the flow field and magnetic field inclination of the symmetric sunspot, NOAA 10425, August 9, 2003. a) Inclination angle of the flow field; b) inclination angle of the magnetic field. Vertical dashed lines show the limits of umbra and penumbra. Symbols are explained in Fig. 13.
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