Astronomy & Astrophysics

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$\begin{figure} \par\includegraphics[width=12.8cm,clip]{ms3957f1.eps}\end{figure}$ Figure 1: Continuum intensity image of the observed sunspot. The white contour marks the umbral-penumbral, the dark contour the penumbral-quiet Sun boundaries. The intensity is normalized to the average quiet Sun intensity. The asterisks symbol inside the circle show the locations of the umbral (1), penumbral (2) and neutral-line (3) profiles shown in Fig. 6.
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In the text

$\begin{figure} \par\includegraphics[width=13.2cm,clip]{ms3957f2.eps}\end{figure}$ Figure 2: Sample Stokes I profiles for a quiet Sun (solid) and umbral (dotted) point. The umbral profile clearly shows the OH lines blending with the Fe I 15 652.8 Å.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f3a.eps}\vspace*{3mm} \includegraphics[width=8.8cm,clip]{ms3957f3b.eps}\end{figure}$ Figure 3: Response functions of Stokes I and V (gray scale) to the magnetic field strength (B) as a function of wavelength and logarithmic optical depth, evaluated for the umbral atmosphere shown in Fig. 7.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f4a.eps}\vspace*{3mm} \includegraphics[width=8.8cm,clip]{ms3957f4b.eps}\end{figure}$ Figure 4: Response functions of Stokes I and V (gray scale) to the LOS velocity (v $_{{\rm LOS}}$ ) as a function of wavelength and logarithmic optical depth, evaluated for the umbral atmosphere shown in Fig. 7.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f5a.eps}\vspace*{3mm} \includegraphics[width=8.8cm,clip]{ms3957f5b.eps}\end{figure}$ Figure 5: Response functions of Stokes Q and V (gray scale) to magnetic field inclination $(\gamma )$ as a function of wavelength and logarithmic optical depth, evaluated for the umbral atmosphere shown in Fig. 7.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{ms3957f6a.eps}\vspace*{3mm... ...eps}\vspace*{3mm} \includegraphics[width=8.7cm,clip]{ms3957f6c.eps}\end{figure}$ Figure 6: Typical fits obtained from the inversion (dots) of Stokes profiles observed (solid curves) at an umbral location (top 4 frames), at the neutral line in the limb-side penumbra (middle 4 frames) and at a point in the center-side penumbra (bottom 4 frames).
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In the text

$\begin{figure} \par\includegraphics[width=8.7cm,clip]{ms3957f7a.eps}\vspace*{5mm} \includegraphics[width=8.7cm,clip]{ms3957f7b.eps}\end{figure}$ Figure 7: Atmospheric stratification obtained from the profiles shown in Fig. 6. Top 4 frames: for the umbral point. Bottom 4 frames: for the point at the neutral line (solid lines) and for the center-side penumbral point (dotted lines). Bars indicate the formal errors of the inversion at the nodes. $\gamma$ denotes the field inclination with respect to the line-of-sight and positive values of the LOS velocity indicate redshifts.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{ms3957f8a.eps}\vspace*{3mm} \includegraphics[width=8.7cm,clip]{ms3957f8b.eps}\end{figure}$ Figure 8: Top 4 frames: fits (dots) to Stokes profiles observed (solid line) for the same umbral location as in Fig. 6, but now without including the Fe I line at 15 652.8 Å and the blending OH lines in the inversion. Bottom 4 frames: The atmospheric stratification returned by the inversion without fitting Fe I line at 15 652.8 Å and the blending OH lines (dotted lines), and when these two are included (solid lines). The respective error in the estimation of these parameters are indicated by the bars. Dashed and dotted-dashed lines in the temperature plot represent the temperature of the stray-light component with and without including the OH lines in the inversions, respectively. $\gamma$ denotes the field inclination with respect to the line-of-sight and positive values of the LOS velocity indicate redshifts.
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In the text

$\begin{figure} \par\includegraphics[width=8.7cm,clip]{ms3957f9.eps}\end{figure}$ Figure 9: Normalized continuum intensity versus temperature obtained from the inversion. Umbral points are denoted by filled circles and penumbral points by plus signs. Gray circles denote the retrieved temperature of the umbral points without fitting the Fe I line at 15 652.8 Å blended with molecular OH lines.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f10.eps}\end{figure}$ Figure 10: Atmospheric stratification of field strength B, line-of-sight velocity $v_{{\rm LOS}}$ , field azimuth $\chi$ , and line-of-sight field inclination $\gamma$ . The shaded area indicates the standard deviation of these parameters for inversions starting from different initial values. Error bars indicate the average formal errors returned by one such inversion (solid lines). The values within the optical depth range enclosed by the vertical dotted lines are used to produce the maps of various parameters.
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In the text

$\begin{figure} \par\includegraphics[width=17.7cm,clip]{ms3957f11.eps}\end{figure}$ Figure 11: Maps of the magnetic field strength (B), as well as of the vertical (B_z) and radial (B_r) field components from top to bottom. For each parameter three maps representing the log $\tau _5$ layer 0 to -0.5, -0.5 to -1.0 and -1.0 to -1.5 are plotted (from left to right). The contours represent the umbral and penumbral boundaries derived from the continuum intensity. The arrow in the lower-left panel marks the direction to solar disk center.
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In the text

$\begin{figure} \par\includegraphics[width=17.7cm,clip]{ms3957f12.eps}\end{figure}$ Figure 12: Same as Fig. 5, but for the zenith angle ( $\zeta$ ), field azimuth ( $\psi$ ) and line-of-sight velocity ( $v_{{\rm LOS}}$ ). The velocity map is clipped to $\pm$ 2 km s $\rm {^{-1}}$ in order to enhance the contrast.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{ms3957f13a.eps}\hspace*{5mm} \includegraphics[width=7.9cm,clip]{ms3957f13b.eps}\end{figure}$ Figure 13: a) Filling factor $\alpha$ for the magnetic component, and b) the zenith angle map for the lowest layer. The dark dotted contour in b) shows the azimuthal path considered in Fig. 14, and the arrows indicate locations identified as "spines".
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f14.eps}\end{figure}$ Figure 14: Variation of B, $v_{{\rm LOS}}$ , $\zeta$ , $\Delta \psi$ and T as a function of position angle along an azimuthal path in the outer penumbra for deep layers. The solid vertical and dotted lines represents local maxima in $\vert v_{{\rm LOS}}\vert$ and minima in $\zeta$ , respectively. The arrows point to locations exhibiting a spine structure. The thick vertical dashed line indicates position angle 180 $^\circ$ .
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{ms3957f15a.eps}\hspace*{1cm}... ...eps}\hspace*{1.1cm} \includegraphics[width=8cm,clip]{ms3957f15d.eps}\end{figure}$ Figure 15: The azimuthal averages for various parameters in the observed sunspot. The vertical lines represent the umbral and penumbral boundaries. The stripes/shaded areas represent the rms variation of these parameters along each radial path. For clarity the rms is indicated only for the top and bottom layers (bottom layer only for line-of-sight velocity).
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In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{ms3957f16.eps}\end{figure}$ Figure 16: Azimuthal averages of the normalized continuum intensity ( $I/I_{\rm Quiet\/Sun}$ ) and scattered light parameter ( $1-\alpha$ ). The vertical lines represent the umbral and penumbral boundaries. The stripes represent the rms variation of these parameters.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f17.eps}\end{figure}$ Figure 17: Average umbral and penumbral stratification obtained from the inversion. The solid line represents the umbral average and dotted line the penumbral average. In the $v_{{\rm LOS}}$ plot (lower right frame) the dot-dashed and dashed line represent the limb-side and center-side average velocities. The dot-dashed line in the temperature plot represents the Kurucz quiet Sun model.
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In the text

$\begin{figure} \par\includegraphics[width=17.8cm,clip]{ms3957f18.eps}\end{figure}$ Figure 18: Test inversion of visible and infrared lines, computed using a two magnetic component flux-tube model atmosphere. Solid curves and dots in the bottom-eight frames display the synthetic profiles and the fits obtained from the single magnetic component inversions. Top three frames show the two component flux-tube model (dot-dashed curves - the flux-tube model, dotted curves - the background) used for the synthesis, and the returned atmospheres for visible (dashed curves) and infrared lines (solid curves) when inverted with a single magnetic component. The shaded area represents the standard deviation of these parameters for inversions starting from different initial values. The asterisks symbols show the locations of nodes used in the inversions.
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In the text

$\begin{figure} \par\includegraphics[width=12.8cm,clip]{ms3957f1.eps}\end{figure}$	Figure 1: Continuum intensity image of the observed sunspot. The white contour marks the umbral-penumbral, the dark contour the penumbral-quiet Sun boundaries. The intensity is normalized to the average quiet Sun intensity. The asterisks symbol inside the circle show the locations of the umbral (1), penumbral (2) and neutral-line (3) profiles shown in Fig. 6.
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$\begin{figure} \par\includegraphics[width=13.2cm,clip]{ms3957f2.eps}\end{figure}$	Figure 2: Sample Stokes I profiles for a quiet Sun (solid) and umbral (dotted) point. The umbral profile clearly shows the OH lines blending with the Fe I 15 652.8 Å.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f3a.eps}\vspace*{3mm} \includegraphics[width=8.8cm,clip]{ms3957f3b.eps}\end{figure}$	Figure 3: Response functions of Stokes I and V (gray scale) to the magnetic field strength (B) as a function of wavelength and logarithmic optical depth, evaluated for the umbral atmosphere shown in Fig. 7.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f4a.eps}\vspace*{3mm} \includegraphics[width=8.8cm,clip]{ms3957f4b.eps}\end{figure}$	Figure 4: Response functions of Stokes I and V (gray scale) to the LOS velocity (v $_{{\rm LOS}}$ ) as a function of wavelength and logarithmic optical depth, evaluated for the umbral atmosphere shown in Fig. 7.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f5a.eps}\vspace*{3mm} \includegraphics[width=8.8cm,clip]{ms3957f5b.eps}\end{figure}$	Figure 5: Response functions of Stokes Q and V (gray scale) to magnetic field inclination $(\gamma )$ as a function of wavelength and logarithmic optical depth, evaluated for the umbral atmosphere shown in Fig. 7.
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$\begin{figure} \par\includegraphics[width=8.5cm,clip]{ms3957f6a.eps}\vspace{3mm... ...eps}\vspace{3mm} \includegraphics[width=8.7cm,clip]{ms3957f6c.eps}\end{figure}$	Figure 6: Typical fits obtained from the inversion (dots) of Stokes profiles observed (solid curves) at an umbral location (top 4 frames), at the neutral line in the limb-side penumbra (middle 4 frames) and at a point in the center-side penumbra (bottom 4 frames).
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$\begin{figure} \par\includegraphics[width=8.7cm,clip]{ms3957f9.eps}\end{figure}$	Figure 9: Normalized continuum intensity versus temperature obtained from the inversion. Umbral points are denoted by filled circles and penumbral points by plus signs. Gray circles denote the retrieved temperature of the umbral points without fitting the Fe I line at 15 652.8 Å blended with molecular OH lines.
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$\begin{figure} \par\includegraphics[width=17.7cm,clip]{ms3957f12.eps}\end{figure}$	Figure 12: Same as Fig. 5, but for the zenith angle ( $\zeta$ ), field azimuth ( $\psi$ ) and line-of-sight velocity ( $v_{{\rm LOS}}$ ). The velocity map is clipped to $\pm$ 2 km s $\rm {^{-1}}$ in order to enhance the contrast.
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$\begin{figure} \par\includegraphics[width=7.9cm,clip]{ms3957f13a.eps}\hspace*{5mm} \includegraphics[width=7.9cm,clip]{ms3957f13b.eps}\end{figure}$	Figure 13: a) Filling factor $\alpha$ for the magnetic component, and b) the zenith angle map for the lowest layer. The dark dotted contour in b) shows the azimuthal path considered in Fig. 14, and the arrows indicate locations identified as "spines".
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$\begin{figure} \par\includegraphics[width=8cm,clip]{ms3957f15a.eps}\hspace{1cm}... ...eps}\hspace{1.1cm} \includegraphics[width=8cm,clip]{ms3957f15d.eps}\end{figure}$	Figure 15: The azimuthal averages for various parameters in the observed sunspot. The vertical lines represent the umbral and penumbral boundaries. The stripes/shaded areas represent the rms variation of these parameters along each radial path. For clarity the rms is indicated only for the top and bottom layers (bottom layer only for line-of-sight velocity).
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$\begin{figure} \par\includegraphics[width=8.6cm,clip]{ms3957f16.eps}\end{figure}$	Figure 16: Azimuthal averages of the normalized continuum intensity ( $I/I_{\rm Quiet\/Sun}$ ) and scattered light parameter ( $1-\alpha$ ). The vertical lines represent the umbral and penumbral boundaries. The stripes represent the rms variation of these parameters.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{ms3957f17.eps}\end{figure}$	Figure 17: Average umbral and penumbral stratification obtained from the inversion. The solid line represents the umbral average and dotted line the penumbral average. In the $v_{{\rm LOS}}$ plot (lower right frame) the dot-dashed and dashed line represent the limb-side and center-side average velocities. The dot-dashed line in the temperature plot represents the Kurucz quiet Sun model.
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