Camera for Quasars in Early Universe (CQUEAN)

• Published in: Publications of the Astronomical Society of the Pacific 2012-08, Vol.124 (918), p.839-853
• Main Authors: PARK, Won-Kee, PAK, Soojong, IM, Myungshin, CHOI, Changsu, JEON, Yiseul, CHANG, Seunghyuk, JEONG, Hyeonju, LIM, Juhee, KIM, Eunbin
• Format: Article
• Language: English
• Subjects: Astronomy; Earth, ocean, space; Exact sciences and technology; Gamma-ray bursts; Quasars; Stellar investigations; Telescopes; Universe
• ISSN: 0004-6280
• DOI: 10.1086/667390

We describe the overall characteristics and the performance of an optical CCD camera system, Camera for Quasars in Early Universe (CQUEAN), which has been used at the 2.1 m Otto Struve Telescope of the McDonald Observatory since 2010 August. CQUEAN was developed for follow-up imaging observations of red sources such as high-redshift quasar candidates ( ? 5 ), gamma-ray bursts, brown dwarfs, and young stellar objects. For efficient observations of the red objects, CQUEAN has a science camera with a deep-depletion CCD chip, which boasts a higher quantum efficiency at 0.7-1.1 mu m than conventional CCD chips. The camera was developed in a short timescale and has been working reliably. By employing an autoguiding system and a focal reducer to enhance the field of view on the classical Cassegrain focus, we achieve a stable guiding in 20 minute exposures, an imaging quality with FWHM=0.6 over the whole field ( 4.8 X 4.8 ), and a limiting magnitude of = 23.4 AB mag at 5-s with 1 hr total integration time.