deepCR宇宙线识别方法在CSST巡天数据处理中的可用性及稳定性定量评价研究

A Study on Quantitative Assessment of Usability and Stability for deepCR Cosmic Ray Identification Methods in CSST Survey Data Processing

deepCR宇宙线识别方法是哈勃空间望远镜(Hubble Space Telescope,HST)剔除宇宙线的有效方法,但这一方法是否可以满足中国空间站望远镜(China Space Station Telescope,CSST)的要求,始终缺乏科学的定量分析。采用哈勃望远镜的真实观测数据,对deepCR宇宙线识别方法进行了深入分析,对其稳定性和可用性进行了实测研究。结果表明,deepCR在天空背景区域识别宇宙线的灵敏度较高,但越靠近星像中心,deepCR识别宇宙线的灵敏度越低。分析了宇宙线密度和测光精度的关系,发现当宇宙线密度达到9%时,几乎100%的星受到宇宙线的污染;当宇宙线密度达到14%时,对于不同轮廓面积的星,存在20%~50%的异常测光结果。实验结果表明,deepCR宇宙线识别模型稳定性相对较好,一次建模后可以在较长时间内应用。但在高精度测光等应用场景仍面临着一系列问题,需要有针对性的解决方案。

The deepCR cosmic ray identification method could effectively remove cosmic rays from the Hubble Space Telescope(HST).However,there needs to be more quantitative analysis on whether this method can meet the China Space Telescope(CSST)requirements.In this paper,we analyze the deepCR cosmic ray method in-depth using real observational data from the Hubble Telescope.We conducted an empirical study of its stability and usability.The results show that deepCR performs well in identifying the cosmic ray in the sky background region,but its sensitivity decreases as it approaches to the centre of star.We analyze the correlation between the cosmic ray density and the photometric accuracy,demonstrating that when the cosmic ray density reaches 9%,alomost all stars(100%)are contaminated by cosmic rays;when the cosmic ray density reaches 14%,there are abnormal photometric results(20%-50%)for stars with different contour areas.The analysis shows that the deepCR cosmic ray identification model is relatively stable and can be applied over a longer period of time after one model.However,it still faces a series of problems in application scenarios,such as high-precision photometry,which need to be addressed in the near future.