X-ray selected AGNs behind the SMC

Finding Active Galactic Nuclei (AGNs) behind the Magellanic Clouds is difficult because of the high stellar density in these fields. Although the first AGNs behind the Small Magellanic Cloud (SMC) was reported in the 1980's, it is only recently that the number of AGNs behind the SMC has increased by several orders of magnitude. AGNs behind the SMC are of several scientific interests, including an astrometric reference system needed to derive precise coordinates, especially for proper motion studies. The mid-infrared color selection technique has been proven to be an efficient mean of identifying AGNs, especially obscured sources. The X-ray regime is also complimentary in this regard. We present a catalog of AGNs behind the SMC by correlating the XMM-Newton X-ray point source catalog of the SMC with already known AGNs from literature, as well as candidates obtained from the ALLWISE mid-infrared color selection criterion. The redshift and luminosity distribution of the sample indicate that we detect sources from nearby Seyfert galaxies to distant and obscured quasars. The X-ray hardness ratios are compatible with those typically expected for AGNs. The near-infrared colors and variability are also consistent in this regard. We also present a sample of new candidate AGNs and candidates for highly obscured AGNs. All of these make an interesting subset for further follow-up studies.