Towards a fundamental astrometric reference system behind the Malleganic clouds : spectroscopic confirmation of new quasar candidates selected in the near-infrared

Ivanov, Valentin D.; Cioni, Maria-Rosa Lucia; Bekki, Kenji; De Grijs, Richard; Emerson, Jim; Gibson, Brad K.; Kamath, Devika; Van Loon, Jacco Th; Piatti, Andrés; For, Bi-Qing

Abstract

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. We have embarked on a programme to expand the quasar reference system behind the Large and Small Magellanic Clouds, the Magellanic Bridge and Magellanic Stream. Hundreds of quasar candidates were selected, based on their near-infrared colours and variability properties from the ESO VISTA Magellanic Clouds (VMC) Public Survey. A subset of 49 objects was followed up with optical spectroscopy with FORS2. We confirmed the quasar nature of 37 objects (34 new identifications) that span a redshift range from z ~ 0.5 to 4.1.

• Journal Article Type: Article
• Publication Date: Oct 3, 2016
• Journal: ESO messenger
• Print ISSN: 0722-6691
• Publisher: European Southern Observatory
• Peer Reviewed: Not Peer Reviewed
• Issue: 163
• Pages: 32-34
• APA6 Citation: Ivanov, V. D., Cioni, M. L., Bekki, K., De Grijs, R., Emerson, J., Gibson, B. K., …For, B. (2016). Towards a fundamental astrometric reference system behind the Malleganic clouds : spectroscopic confirmation of new quasar candidates selected in the near-infrared. The Messenger, 32-34
• Keywords: Quasars
• Publisher URL: https://www.eso.org/sci/publications/messenger/archive/no.163-mar16/messenger-no163-32-34.pdf
• Additional Information: This is a copy of an article published in ESO Messenger, 2016, issue 163.