the simulations are consistent with those found by fitting [*Chandra*]{}/HEG data in the quasar regime for the $\theta_{\mathrm{OA}}-L_{\mathrm{X}}$ relationship of @Maiolino:2007bh for $N_{\rm\,H}^{\rm\,T}\geq 10^{23.7}\rm\,cm^{-2}$. The values of the slope expected using the relationship of @Hasinger:2008ve are steeper than the observed value for the whole range of column densities considered, while the flattening of the relationship of @Burlon:2011cr at high luminosities results in a slope of $B\sim0$ along the whole range of $N_{\rm\,H}^{\rm\,T}$, consistent within 1$\sigma$ with the observations. The intercepts obtained using the relationship of @Maiolino:2007bh are consistent with the observed value for $22.5 \leq \log N_{\rm\,H}^{\rm\,T} \leq 23.1$ (right panel of Fig.\[fig:interc\_sy\_2\]), with no overlap with the values of $N_{\rm\,H}^{\rm\,T}$ needed by the slope. We obtained intercepts that are consistent with the observations for $ 22.7 \lesssim \log N_{\rm\,H}^{\rm\,T}\lesssim 23.4$ and $23.2 \lesssim \log N_{\rm\,H}^{\rm\,T}\lesssim 24.2$ for the relation of @Hasinger:2008ve and @Burlon:2011cr, respectively. Thus only the hard X-ray $\theta_{\mathrm{OA}}-L_{\mathrm{X}}$ relationship @Burlon:2011cr is able to explain, for average values of the equatorial column density of the torus in the range $23.2 \lesssim \log N_{\rm\,H}^{\rm\,T}\lesssim 24.2$, at the same time both the intercept and the slope of the X-ray Baldwin effect at high luminosities.

Discussion {#Sec:discussion}
==========

Since its discovery 