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In this work, which is a continuation of Castell\'o-Mor et al. (2016), wepresent new X-ray and infrared (IR) data for a sample of active galactic nuclei(AGN) covering a wide range in Eddington ratio over a small luminosity range.In particular, we rigorously explore the dependence of the optical-to-X-rayspectral index $\alpha_{OX}$ and the IR-to-optical spectral index on thedimensionless accretion rate, $\dot{\mathcal{M}}=\dot{m}/\eta$ where$\dot{m}=L_{AGN}/L_{Edd}$ and $\eta$ is the mass-to-radiation conversionefficiency, in low and high accretion rate sources. We find that the SED of thefaster accreting sources are surprisingly similar to those from the comparisonsample of sources with lower accretion rate. In particular: i) theoptical-to-UV AGN SED of slow and fast accreting AGN can be fitted with thin ADmodels. ii) The value of $\alpha_{OX}$ is very similar in slow and fastaccreting systems up to a dimensionless accretion rate$\dot{\mathcal{M}}_{c}\sim$10. We only find a correlation between $\alpha_{OX}$and $\dot{\mathcal{M}}$ for sources with $\dot{\mathcal{M}} >\dot{\mathcal{M}}_{c}$. In such cases, the faster accreting sources appear tohave systematically larger $\alpha_{OX}$ values. iii) We also find that thetorus in the faster accreting systems seems to be less efficient inreprocessing the primary AGN radiation having lower IR-to-optical spectralslopes.  These findings, failing to recover the predicted differences between the SEDsof slim and thin ADs within the observed spectral window, suggest thatadditional physical processes or very special geometry act to reduce theextreme UV radiation in fast accreting AGN. This may be related to photontrapping, strong winds, and perhaps other yet unknown physical processes.

Unveiling slim accretion disc in AGN through X-ray and Infrared observations