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Related papers: Variability-selected quasars behind the Small Mage…

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We present the discovery of nine quasars behind the Large Magellanic Cloud, with emission redshifts ranging from 0.07 to 2.0. Six of them were identified as part of the systematic variability-based search for QSOs in the objects from the…

Astrophysics · Physics 2008-11-07 A. Dobrzycki , L. Eyer , K. Z. Stanek , L. M. Macri

We present 47 spectroscopically-confirmed quasars discovered behind the Magellanic Clouds identified via photometric variability in the MACHO database. Thirty-eight quasars lie behind the Large Magellanic Cloud and nine behind the Small…

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Szymon Kozlowski , Christopher S. Kochanek , Andrzej Udalski

Quasi--stellar objects (quasars) located behind nearby galaxies provide an excellent absolute reference system for astrometric studies, but they are difficult to identify because of fore- and background contamination. Deep wide--field, high…

A search for faint slowly variable objects was undertaken in the hope of finding QSO candidates behind the Small and Large Magellanic Clouds (SMC and LMC). This search used the optical variability properties of point sources from the…

Astrophysics · Physics 2007-05-23 Laurent Eyer

We present five X-ray quasars behind the Small Magellanic Cloud, increasing the number of known quasars behind the SMC by ca. 40%. They were identified via follow-up spectroscopy of serendipitous sources from the Chandra X-ray Observatory…

Astrophysics · Physics 2008-11-07 A. Dobrzycki , K. Z. Stanek , L. M. Macri , P. J. Groot

We report the identification of blazar candidates behind the Magellanic Clouds. The objects were selected from the Magellanic Quasars Survey (MQS), which targeted the entire Large Magellanic Cloud (LMC) and 70\% of the Small Magellanic…

Quasi-stellar objects (QSOs) are a basis for an absolute reference system for astrometric studies. There is a need for creating such system behind nearby galaxies, to facilitate the measuring of the proper motions of these galaxies.…

Data are given for 16 extragalactic objects (predominantly AGN) behind the Magellanic Clouds and for 146 quasar candidates behind the nearby galaxies NGC 45, 185, 253, 2366, 2403 and 6822, IC 1613, M31 and M33. The Magellanic Cloud objects…

Astrophysics · Physics 2009-10-30 David Crampton , G. Gussie , A. P. Cowley , P. C. Schmidtke

We present the discovery of four X-ray quasars (z_em = 0.26, 0.53, 0.61, 1.63) located behind the Large Magellanic Cloud; three of them are located behind the bar of the LMC. The quasars were identified via spectroscopy of optical…

Astrophysics · Physics 2016-08-30 A. Dobrzycki , P. J. Groot , L. M. Macri , K. Z. Stanek

The Magellanic Quasars Survey (MQS) has now increased the number of quasars known behind the Magellanic Clouds by almost an order of magnitude. All survey fields in the Large Magellanic Cloud (LMC) and 70% of those in the Small Magellanic…

We quadruple the number of quasars known behind the Large Magellanic Cloud (LMC) from 55 (42 in the LMC fields of the third phase of the Optical Gravitational Lensing Experiment (OGLE)) to 200 by spectroscopically confirming 169 (144 new)…

We report the discovery of 5 new Herbig Ae/Be candidate stars in the Small Magellanic Cloud in addition to the 2 reported in Beaulieu et al. (2001). We discuss these 7 HAeBe candidate stars in terms of (1) their irregular photometric…

Astrophysics · Physics 2009-11-10 W. J. de Wit , J-P. Beaulieu , H. J. G. L. M. Lamers , E. Lesquoy , J-B. Marquette , ;

We present a combined analysis of the optical spectral variability for two samples of QSOs, 42 objects at $z<0.4$ monitored at the Wise Observatory (Giveon et al 1999), plus 59 objects up to $z\sim 3$ in the field of the Magellanic Clouds,…

Astrophysics · Physics 2007-05-23 F. Vagnetti , D. Trevese

We have used deep Optical Gravitational Lensing Experiment (OGLE-IV) images ($V \lesssim 23$ mag, $I \lesssim 23$ mag at $3\sigma$) of the Magellanic System, encompassing an area of $\sim$670 deg$^2$, to perform a search for high-$z$ quasar…

Studies of young stellar objects (YSOs) in the Galaxy have found that a significant fraction exhibit photometric variability. However, no systematic investigation has been conducted on the variability of extragalactic YSOs. Here we present…

The number and spatial distribution of confirmed quasi-stellar objects (QSOs) behind the Magellanic system is limited. This undermines their use as astrometric reference objects for different types of studies. We have searched for criteria…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 M. -R. L. Cioni , D. Kamath , S. Rubele , J. Th. van Loon , P. R. Wood , J. P. Emerson , B. K. Gibson , M. A. T. Groenewegen , V. D. Ivanov , B. Miszalski , V. Ripepi

H\alpha and [O III] narrow band, wide field (7 * 7 degree), CCD images of the Small Magellanic Cloud were compared and a catalogue of candidate planetary nebulae and H\alpha emission-line stars was compiled. The catalogue contains 131…

Astrophysics · Physics 2009-10-31 Michael T. Murphy , Michael S. Bessell

We present an optical variability study of 44 newly identified blazar candidates behind the Magellanic Clouds, including 27 flat spectrum radio quasars (FSRQs) and 17 BL Lacertae objects (BL Lacs). All objects in the sample possess high…

Astrophysics of Galaxies · Physics 2020-01-29 Natalia Żywucka , Mariusz Tarnopolski , Markus Böttcher , Łukasz Stawarz , Volodymyr Marchenko

The data of 8,852 and 2,927 variable stars detected by OGLE survey in the Large and Small Magellanic Clouds are presented. They are cross-identified with the SIRIUS JHK survey data, and their infrared properties are discussed. Variable red…

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