We present high angular resolution (~0.''5) MIR spectra of the powerful radio galaxy, Cygnus A (Cyg A), obtained with the Subaru telescope. The overall shape of the spectra agree with previous high angular resolution MIR observations, as well as previous Spitzer spectra. Our spectra, both on and off nucleus, show a deep silicate absorption feature. The absorption feature can be modeled with a blackbody obscured by cold dust or a clumpy torus. The deep silicate feature is best fit by a simple model of a screened blackbody, suggesting that foreground absorption plays a significant, if not dominant, role in shaping the spectrum of Cyg A. This foreground absorption prevents a clear view of the central engine and surrounding torus, making it difficult to quantify the extent the torus attributes to the obscuration of the central engine, but does not eliminate the need for a torus in Cyg A.
Digital Object Identifier (DOI)
M.J.M. and E.S.P acknowledge support from NSF grant AST-0904890. C.P. acknowledges support from NFS grant AST-0904421. M.E. acknowledges support from NFS grant AST-0904316.
Merlo, Matthew J.; Perlman, Erik S.; Nikutta, Robert; Packham, Christopher; Elitzur, Moshe; Imanishi, Masatoshi; Levenson, N. A.; Radomski, James T.; and Aretxaga, Itziar, "Subaru Spectroscopy and Spectral Modeling of Cygnus A" (2014). Physics and Astronomy Faculty Publications. 186.