All Figures

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{1667fig1.eps} \end{figure}$ Figure 1: Wavelength dependence of the anisotropy factor k_G for $\mu =0.1$ . Note that the effective Balmer jump occurs at substantially longer wavelengths than the actual series limit (marked by the vertical line).
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In the text

$\begin{figure} \par\includegraphics[width=12cm]{1667fig2.eps} \end{figure}$ Figure 2: Lyman scattering opacity per hydrogen atom, in units of the Thomson scattering cross section per electron. The dashed curve represents the analytic expression of Eq. (46), which is an excellent approximation above 2000 Å. Below the Lyman limit the scattering behaves as if the excited electron were free (like Thomson scattering), while the cross section for radiative ionization (dash-dotted curve) is many orders of magnitude larger.
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In the text

$\begin{figure} \par\includegraphics[width=13cm,clip]{1667fig3.eps} \end{figure}$ Figure 3: Main contributors to the Sun's continuum opacity in the visible and near UV. The lower solid curve represents the Balmer scattering cross section, while the upper solid curve gives the cross section for bound-bound radiative absorption. Pressure broadening due to the statistical Stark effect is accounted for to describe convergence of the bound-bound opacities to the bound-free ones. Comparison is made with the Lyman scattering cross section (dashed), the Thomson scattering cross section (horizontal solid line), the H^- opacity (dotted), and the bound-free opacity for radiative ionization (dash-dotted). The relative contributions of these opacity sources depend on the electron densities and pressures and the relative level populations of hydrogen. The values chosen are typical for solar conditions.
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In the text

$\begin{figure} \par\includegraphics[width=12cm,clip]{1667fig4.eps} \end{figure}$ Figure 4: Illustration of a 2-parameter fit to the observed Q/I with the model given by Eq. (71), assuming that $\alpha =0.6$ . The thick solid lines represent the observations (taken from the currently unpublished UV portion of Gandorfer's Atlas of the Second Solar Spectrum), while the thin curves represent the model. The determined level of the continuum polarization $p_{\rm c}$ is given by the horizontal line in the bottom panel.
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In the text

$\begin{figure} \par\includegraphics[width=12.5cm,clip]{1667fig5.eps} \end{figure}$ Figure 5: Continuum polarization $p_{\rm c}$ , as determined from the Atlas of the Second Solar Spectrum using the model of Eq. (68). Asterisks represent model fits with $\alpha =1.0$ , filled circles fits with $\alpha =0.6$ , open circles fits with $\alpha =0.3$ . The vertical lines give the resonance wavelengths of the first ten Balmer lines, plus the series limit as the left-most vertical line. The three solid curves represent second-order polynomial fits to the $\log p_{\rm c}$ values: a central curve as the most likely representation, and two outer curves that indicate the approximate lower and upper limits.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{1667fig6.eps} \end{figure}$ Figure 6: Comparison between observations and theory. The shaded area represents the empirically allowed region, defined as the region between the two outer polynomial curves in Fig. 5. The vertical line marks the wavelength of the Balmer series limit. The dashed curve has been obtained from the radiative-transfer theory of Fluri & Stenflo (1999). The thick, solid curve is based on the last scattering approximation, Eq. (72), with the anisotropy and the opacities given by Figs. 1 and 3. Note in particular the large displacement of the Balmer jump with respect to the series limit.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{1667fig7.eps} \end{figure}$ Figure 7: Overview of the functional behavior of the empirically determined continuum polarization $p_{\rm c}$ . The two upper panels give the wavelength variation of $p_{\rm c}$ for $\mu =0.1$ , in logarithmic and linear scales. The curves are the same as the central polynomial curve in Fig. 5. The two bottom panels give the center-to-limb variation of $p_{\rm c}$ for $\lambda =4000$ Å, in logarithmic and linear scales.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{1667fig1.eps} \end{figure}$	Figure 1: Wavelength dependence of the anisotropy factor k_G for $\mu =0.1$ . Note that the effective Balmer jump occurs at substantially longer wavelengths than the actual series limit (marked by the vertical line).
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