Probing the Circumnuclear Environment of NGC 7582 Through Water Ice Absorption

Recent JWST mid-infrared observations of the Seyfert 2 nucleus of NGC 7582 (within the central ~50 pc) have revealed prominent ice absorption features that are not reproduced by existing AGN dust radiative transfer models. In particular, template spectra from the AGN model library of Siebenmorgen et al. (2014) fail to produce the observed ice signatures and underestimate the flux level by a factor of compared to the JWST spectrum. To address this discrepancy, we propose a new class of frosty AGN models that incorporate icy grain mantles within a clumpy dust torus. By implementing Monte Carlo radiative transfer calculations, we include both the effect of embedded ice features and the contribution of additional heating spectra from type-I quasars, thereby extending and updating the current AGN model libraries. This framework allows us to tackle several key scientific questions: At what radius in the accretion disk does the snow line emerge? Under what conditions can water freeze out onto dust particles in AGN environments? Is the ice reservoir preferentially located within the accretion disk, in clumps, or in the inner/outer torus regions? Beyond these physical insights, our work also addresses the broader puzzle of why current AGN models fail so severely in reproducing the JWST mid-infrared data. Our findings highlight the need to revise torus models to include icy dust components, which may fundamentally alter our interpretation of AGN spectral energy distributions and their role in galaxy evolution.