All Figures

$\begin{figure} \par\includegraphics[angle=-90,width=7.9cm,clip]{0118Fig1.ps}\end{figure}$ Figure 1: The spectral index $\Gamma$ of the S1 sources as a function of redshift.
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In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{0118Fig2.ps} % \end{figure}$ Figure 2: The X-ray spectral count distributions of two sources with comparable 2-10 keV fluxes. At the top the unabsorbed source 03120020, at the bottom the source 03120016, which is evidently affected by strong absorption.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{0118Fig3.ps} % \end{figure}$ Figure 3: The distribution as a function of F_u of the sources in the sample. See text for the sources excluded from this plot. In black the sources with $N_{\rm H}>10^{23}$ cm^-2, in gray those with $N_{\rm H}$ between 10²² and 10²³ cm^-2, in white those with $N_{\rm H}<10^{22}$ cm^-2.
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In the text

$\begin{figure} \par\includegraphics[width=7.4cm,clip]{0118Fig4.ps} % \end{figure}$ Figure 4: The fraction of sources with $N_{\rm H}>10^{22}$ cm^-2(68% poissonian errors) as a function of their luminosity. The sources with unknown zare included, as explained in the text. The broken line represents the expectation if such a fraction is intrinsically independent of the luminosity, but see text for comments on this issue in Sects. 4.2 and 5.
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In the text

$\begin{figure} \par\includegraphics[width=8.7cm,clip]{0118Fig5.ps} % \end{figure}$ Figure 5: The X/O distribution for the sources in the sample. In black the sources with $N_{\rm H}>10^{23}$ cm^-2, in gray those with $N_{\rm H}$ between 10²² and 10²³ cm^-2, in white those with $N_{\rm H}<10^{22}$ cm^-2.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=7.3cm,clip]{0118Fig6.ps} % \end{figure}$ Figure 6: The fraction of sources with log $N_{\rm H}$ greater than 22, in the two F_u intervals from Table 6 (full circles), compared with the predictions based on the model (solid line) by Comastri et al. (1995, see also Comastri et al. 2001), and the model B (dashed line) by Gilli et al. (2001). The points in the two lower flux intervals (empty circles) were derived from the CDFN survey (see text).
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=7.3cm,clip]{0118Fig7.ps} % \end{figure}$ Figure 7: The fraction of sources as in Fig. 6, here compared with the prediction which is obtained when, in the Comastri et al. (1995, 2001) model, the $N_{\rm H}$ distribution is changed to a flat one, as described in the text.
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{0118Fig8.ps} % \end{figure}$ Figure A.1: Comparison of the best fit flux with that obtained from the images and used in Paper IV. Open circles are objects with $N_{\rm H}<10^{22}$ cm^-2, filled circles are objects with $N_{\rm H}>10^{22}$ cm^-2. The solid line represents a one to one relationship.

In the text

$\begin{figure} \par\includegraphics[width=8.3cm,clip]{0118Fig9.ps}\end{figure}$ Figure B.1: Comparison of the best fit values of $N_{\rm H}$ (with 90% error bars) to those estimated with the Softness Ratio technique used in Paper IV. The solid line represents a one to one relationship, the two dashed lines divide the figure in four quadrants with log $N_{\rm H}$ higher or lower than 22.

In the text

$\begin{figure} \par\includegraphics[angle=-90,width=7.9cm,clip]{0118Fig1.ps}\end{figure}$	Figure 1: The spectral index $\Gamma$ of the S1 sources as a function of redshift.
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$\begin{figure} \par\includegraphics[width=8.6cm,clip]{0118Fig2.ps} % \end{figure}$	Figure 2: The X-ray spectral count distributions of two sources with comparable 2-10 keV fluxes. At the top the unabsorbed source 03120020, at the bottom the source 03120016, which is evidently affected by strong absorption.
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$\begin{figure} \par\includegraphics[width=8.5cm,clip]{0118Fig3.ps} % \end{figure}$	Figure 3: The distribution as a function of F_u of the sources in the sample. See text for the sources excluded from this plot. In black the sources with $N_{\rm H}>10^{23}$ cm^-2, in gray those with $N_{\rm H}$ between 10²² and 10²³ cm^-2, in white those with $N_{\rm H}<10^{22}$ cm^-2.
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$\begin{figure} \par\includegraphics[width=7.4cm,clip]{0118Fig4.ps} % \end{figure}$	Figure 4: The fraction of sources with $N_{\rm H}>10^{22}$ cm^-2(68% poissonian errors) as a function of their luminosity. The sources with unknown zare included, as explained in the text. The broken line represents the expectation if such a fraction is intrinsically independent of the luminosity, but see text for comments on this issue in Sects. 4.2 and 5.
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$\begin{figure} \par\includegraphics[width=8.7cm,clip]{0118Fig5.ps} % \end{figure}$	Figure 5: The X/O distribution for the sources in the sample. In black the sources with $N_{\rm H}>10^{23}$ cm^-2, in gray those with $N_{\rm H}$ between 10²² and 10²³ cm^-2, in white those with $N_{\rm H}<10^{22}$ cm^-2.
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$\begin{figure} \par\includegraphics[angle=-90,width=7.3cm,clip]{0118Fig7.ps} % \end{figure}$	Figure 7: The fraction of sources as in Fig. 6, here compared with the prediction which is obtained when, in the Comastri et al. (1995, 2001) model, the $N_{\rm H}$ distribution is changed to a flat one, as described in the text.
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