Abstract: Active galactic nuclei (AGN) are supermassive black holes in galaxies which are seen accreting material, making them glow brightly across the electromagnetic spectrum. Seyfert galaxies are a subset of AGN which show strong accretion activity while residing in a detectable host galaxy. Broadly speaking, AGN are classified as type one or two based on their emission properties. The optical spectra of type one AGN are characterized by the presence of broad spectral lines while those of type two AGN are absent of these features and instead host only narrow spectral lines. The canonical unified theory of active galactic nuclei posits that these two main types of AGN are fundamentally the same, distinguished only by the angle between the AGN and the viewer. This means that type two AGN do contain broad line regions, but they are obscured by a dusty torus which encircles the nucleus along the line of sight. However, there is some evidence of so-called “true” type two AGN which break this principle and contain no broad lines in their optical spectra without containing significant absorbing material along the line of sight. This work makes use of archival Chandra X-ray Observatory data identified by the Chandra and Sloan Digital Sky Survey crossmatched database in order to identify unabsorbed sources optically classified as type 2 Seyfert AGN. X-ray spectra were extracted and fit with an absorbed power law model in order to determine the density of absorbing material surrounding the AGN. AGN with absorbing material densities on the order of the galactic interstellar medium were identified and are presented for further study as candidates for identification as true type 2 Seyfert AGN.
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