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تسجيل مستخدم جديدThe Magellanic Quasars Survey. I. Doubling the Number of Known AGNs Behind the Small Magellanic Cloud
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We report the spectroscopic confirmation of 29 new, 12 plausible, and 3 previously known quasars behind the central ~1.5 deg^2 region of the Small Magellanic Cloud. These were identified in a single 2df/AAOmega observation on the Anglo-Australian Telescope of 268 candidates selected primarily based on their mid-IR colors, along with a smaller number of optically variable sources in OGLE-II close to known X-ray sources. The low detection efficiency was partly expected from the high surface density of SMC as compared to the LMC targets and the faintness of many of them (149 with I>20 mag). The expected number of I<20 mag quasars in the field is ~38, and we found 15 (22 with plausible) or 40% (60%). We did not attempt to determine the nature of the remaining sources, although several appear to be new planetary nebulae. The newly discovered AGNs can be used as reference points for future proper motion studies, to study absorption in the interstellar medium, and to study the physics of quasar variability with the existing long-term, highly cadenced OGLE light curves.
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