新疆天文台南山 1 m 宽视场光学望远镜测光系统 postprint

Abstract: The flux calibration of photometry system is an essential and basic work. The main factors which influence the calibrations include the detector response function (photo-metric zero point), colors of the stars and airmass.The Xinjiang Astronomical Observatory’s nanshan one-meter wide-field telescope was used to conduct multi-band observations of the U/B/V/R/I standard star in the Landolt standard field J054610+45 under different airmass, and the atmospheric extinction coefficient was obtained according to the Bouguer’s law. We used the observation data of the standard field from November 29th, 2017 to January 4th, 2019 to obtain photometric zero point as well as color correction items of each band and to make the conversion from the NOWT instrument magnitude to the Landolt standard magnitude, which provides a methodological reference for users to conduct flux calibrations with the telescope in the future. The results show that the flux calibration correction coefficients of different days will fluctuate to a certain extent. In order to obtain better flow calibration results, it is necessary to observe the standard stars every day in order to obtain the flux calibration correction coefficients of the day; On the one hand, considering the limitations of practical observation conditions, the atmospheric extinction coefficient could be considered to be constant for a period of time, and the flux calibration using the average atmospheric extinction coefficient over a period of time can still lead to good calibration results.