The estimate of sensitivity for large infrared telescopes based on measured sky brightness and atmospheric extinction  

作　　者：Zhi-Jun Zhao Hai-Jing Zhou Yu-Chen Zhang Yun Ling Fang-Yu Xu 赵志军;周海静;张雨辰;凌云;许方宇(School of Physics,Henan Normal University,Xinxiang 453007,China;Yunnan Observatories,Chinese Academy of Sciences,Kunming 650216,China;Kunming Institute of Physics,Kunming 650216,China;Henan Key Laboratory of Infrared Materials&Spectrum Measures and Applications,Xinxiang 453007,China)

机构地区：[1]School of Physics,Henan Normal University,Xinxiang 453007,China [2]Yunnan Observatories,Chinese Academy of Sciences,Kunming 650216,China [3]Kunming Institute of Physics,Kunming 650216,China [4]Henan Key Laboratory of Infrared Materials&Spectrum Measures and Applications,Xinxiang 453007,China

出　　处：《Research in Astronomy and Astrophysics》2021年第4期101-109,共9页天文和天体物理学研究（英文版）

基　　金：funded by the National Natural Science Foundation of China(NSFC,Nos.11803089,U1931124)。

摘　　要：In order to evaluate the ground-based infrared telescope sensitivity affected by the noise from the atmosphere,instruments and detectors,we construct a sensitivity model that can calculate limiting magnitudes and signal-to-noise ratio(S/N).The model is tested with tentative measurements of M’-band sky brightness and atmospheric extinction obtained at the Ali and Daocheng sites.We find that the noise caused by an excellent scientific detector and instruments at-135℃can be ignored compared to the M’-band sky background noise.Thus,when S/N=3 and total exposure time is 1 second for 10 m telescopes,the magnitude limited by the atmosphere is 13.01^(m)at Ali and 12.96^(m)at Daocheng.Even under lessthan-ideal circumstances,i.e.,the readout noise of a deep cryogenic detector is less than 200 e-and the instruments are cooled to below-87.2℃,the above magnitudes decrease by 0.056^(m)at most.Therefore,according to observational requirements with a large telescope in a given infrared band,astronomers can use this sensitivity model as a tool for guiding site surveys,detector selection and instrumental thermal-control.

关 键 词：methods:miscellaneous atmospheric effects telescopes site testing instrumentation:detectors instrumentation:miscellaneous 

分 类 号：P111[天文地球—天文学]