KASINICS: Near Infrared Camera System for the BOAO 1.8 m Telescope

Abstract

Abstract We developed Korea Astronomy and Space science Institute (KASI) Near Infrared Camera System (KASINICS) to be installed on the 1.8 m telescope of Bohyunsan Optical Astronomy Observatory (BOAO) in Korea. We use a 512$\times$512 InSb array (Aladdin III Quadrant, Raytheon Co.) to enable $L$ band observations as well as $J, H$, and $K_s$ bands. The field-of-view of the array is 3${\rlap{\hskip.75pt{^\prime}}\hskip.75pt.\hskip1pt}$3$\times$3${\rlap{\hskip.75pt{^\prime}}\hskip.75pt.\hskip1pt}$3 with a resolution of 0${\rlap{\hskip.75pt{^{\prime\prime}}}\hskip.75pt.\hskip1.75pt}$39$/$pixel. We adopt an Offner relay optical system, which provides a cold stop to eliminate thermal background emission from the telescope structures. Most parts of the camera, including the mirrors, were manufactured from the same ingot of aluminum alloy to ensure a homologous contraction from room temperature to 80 K. We also developed a readout electronics system for the array detector. Based on preliminary results from test observations, the limiting magnitudes are $J=$ 17.6, $H=$ 17.5, $K_s =$ 16.1, and $L$(narrow) $=$ 10.0 mag at a signal-to-noise ratio of 10 for an integration time of 100 s.