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arXiv · 1206.2722

Camera for QUasars in EArly uNiverse (CQUEAN)

Won-Kee Park·Soojong Pak·Myungshin Im·Changsu Choi·Yiseul Jeon·Seunghyuk Chang·Hyeonju Jeong·Juhee Lim·Eunbin Kim
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Abstract

We describe the overall characteristics and the performance of an optical CCD camera system, Camera for QUasars in EArly uNiverse (CQUEAN), which is being 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 (z >= 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 um than conventional CCD chips. The camera was developed in a short time scale (~ one year), and has been working reliably. By employing an auto-guiding 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' * 4.8'), and a limiting magnitude of z = 23.4 AB mag at 5-sigma with one hour total integration time.

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Won-Kee Park, Soojong Pak, Myungshin Im, Changsu Choi, Yiseul Jeon, Seunghyuk Chang, Hyeonju Jeong, Juhee Lim, Eunbin Kim. 2012-06-13. Camera for QUasars in EArly uNiverse (CQUEAN). https://doi.org/10.1086/667390

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