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We present results from model fitting to the Spectral Energy Distribution(SED) of a homogeneous sample of Seyfert II galaxies drawn from the $12\mu$mGalaxy Sample. Imaging and nuclear flux measurements are presented in anaccompanying paper (Videla et al., 2013). Here we add IRS Spitzer observationsto further constrain the SEDs after careful subtraction of a starburstcomponent. We use the library of CLUMPY torus models from Nenkova etal.~(2008ab) and also test the two-phase models recently produced by Stalevskiet al.~(2012). We find that photometric and spectroscopic observations in themid-IR (>5mu) are crucial to properly constrain the best-fit torus models.About half of our sources show clear near-IR excess of their SEDs above thebest fit models. This problem can be less severe when using the Stalevski etal.~(2012) models. It is not clear what is the nature of this emission sincebest fitted black body temperatures are very high (~1700-2500 K) and the TypeII classification of our sources would correspond to a small probability topeer directly into the hottest regions of the torus. Crucially, the derivedtorus parameters when using CLUMPY models are quite robust,, independently ofwhether the sources require an additional black body component or not. Ourfindings suggest that tori are characterized by N_0 > 5, sigma > 40, tau < 25,i > 40 degrees, Y < 50 and A_v^los ~ 100-300. From these we can determine thattypical torus sizes and masses of 0.1-5.0 pc and 10^{4-6} M_\odot. We findtentative evidence that those nuclei with a detected Hidden Broad Line Regionsare characterized by lower levels of extinction than those without one.Finally, we find no correlation between the torus properties and the presenceof circumnuclear or more global star-formation.

Modeling the Nuclear Infrared Spectral Energy Distribution of Type II Active Galactic Nuclei