Mock Observations for the CSST Mission: Main Surveys–An Overview of Framework and Simulation Suite
Chengliang Wei, Guoliang Li, Yuedong Fang, Xin Zhang, Yu Luo, Hao Tian, Dezi Liu, Xianmin Meng, Zhang Ban, Xiaobo Li, Zun Luo, Jingtian Xian, Wei Wang, Xiyan Peng, Nan Li, Ran Li, Li Shao, Tianmeng Zhang, Jing Tang, Yang Chen, Zhaoxiang Qi, Zi-Huang Cao, Huanyuan Shan, Nie Lin, Zhaojun Yan, Lei Wang, Zx He, Rui-Biao Luo, Quan-Yu Liu
Abstract
Abstract The Chinese Space Station Survey Telescope (CSST) is a flagship space-based observatory. Its main survey camera is designed to conduct high spatial resolution near-ultraviolet to near-infrared imaging and low-resolution spectroscopic surveys. To maximize the scientific output of CSST, we have developed a comprehensive, high-fidelity simulation pipeline for reproducing both imaging and spectroscopic observations. This paper presents an overview of the simulation framework, detailing its implementation and components. Built upon the GalSim package and incorporating the latest CSST instrumental specifications, our pipeline generates pixel-level mock observations that closely replicate the expected instrumental and observational conditions. The simulation suite integrates realistic astrophysical object catalogs, instrumental effects, point-spread function modeling, and observational noises to produce accurate synthetic data. We describe the key processing stages of the simulation, from constructing the input object catalogs to modeling the telescope optics and detector responses. Furthermore, we introduce the most recent release of simulated datasets, which provide a crucial testbed for data processing pipeline developments, calibration strategies, and scientific analyses, ensuring that CSST will meet its stringent requirements. Our pipeline serves as a vital tool for optimizing CSST main survey strategies and ensuring robust cosmological measurements.