Gain Calibration of an Astronomical CCD Using Fe⁵⁵

The solar X-EUV imaging telescope is under development to meet Chinese needs of space weather research and forecast.Since the CCD serves as a detector of EUV lights and soft X rays, the knowledge of characteristics of the CCD and its calibration are very important for mastering the entire telescope system.In this paper, we describe an experiment of CCD calibration in a cryeogenic vacuum container using radioactive Fe⁵⁵, and list the corresponding data analysis with two methods for the temperature range -8℃ to 0℃.The results from the single- and two-image methods match well and the final gain value is given as the mean of gains at different temperatures.