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تسجيل مستخدم جديدCharacterization and Performance of the Cananea Near-infrared Camera (CANICA)
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We present details of characterization and imaging performance of the Cananea Near-infrared camera (CANICA) at the 2.1m telescope of the Guillermo Haro Astrophysical Observatory (OAGH) located in Cananea, Sonora, Mexico. CANICA has a HAWAII array with a HgCdTe detector of 1024 x 1024 pixels covering a field of view of 5.5 x 5.5 arcmin^2 with a plate scale of 0.32 arcsec/pixel. The camera characterization involved measuring key detector parameters: conversion gain, dark current, readout noise, and linearity. The pixels in the detector have a full-well-depth of 100,000 e- with the conversion gain measured to be 5.8 e-/ADU. The time-dependent dark current was estimated to be 1.2 e-/sec. Readout noise for correlated double sampled (CDS) technique was measured to be 30 e-/pixel. The detector shows 10% non-linearity close to the full-well-depth. The non-linearity was corrected within 1% levels for the CDS images. Full-field imaging performance was evaluated by measuring the point spread function, zeropoints, throughput, and limiting magnitude. The average zeropoint value in each filter are J = 20.52, H = 20.63, and K = 20.23. The saturation limit of the detector is about sixth magnitude in all the primary broadbands. CANICA on the 2.1m OAGH telescope reaches background-limited magnitudes of J = 18.5, H = 17.6, and K = 16.0 for a signal-to-noise ratio of 10 with an integration time of 900s.
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