NVST光栅光谱仪成谱成像数据处理研究

本申请将系统性地研究抚仙湖一米新真空太阳望远镜（NVST）光栅光谱仪狭缝扫描成谱成像数据的高精度处理方法。通过全面测量NVST光谱仪数据中的误差并分析其来源和机制，针对性地研究相应的数据处理解决方案，从而充分挖掘设备的能力，推动NVST的发展。最终目的是为太阳物理学家提供优质的科学数据，提高科学产出。项目将基于前期大量的工作，在四个方面开展深入的研究：光谱数据的预处理、一维成谱数据处理、二维成谱成像数据处理和不同观测模式下数据处理方法的优化。内容包括光谱图像平场改正、几何改正、频漂改正、光谱信噪比提高、不对称仪器轮廓的测量和改正、成谱成像的空间分辨率的改善等。特点和创新点包括：用逐项分离法建立光谱综合平场、用主成分分析法技术提高信噪比、用光球同步像重建二维光谱的单色像。研究成果不仅可以直接应用于NVST光谱仪，同时也为我国未来大型太阳观测设备同类仪器的数据处理提供借鉴。

The proposal will systematically study high precision imaging spectroscopy processing methods for the observation data of the slit scanning grating-spectrograph installed in the New Vacuum Solar Telescope (NVST) at Fuxian Lake. The data processing solution will be provided based on measuring the error of the observation data ，analyzing the error source and error mechanism. We aim to exploit the observation ability of the equipment and promote the development of NVST. Our purpose is to provide high quality scientific data for the solar astronomer, and improve scientific products. The project will study in four areas deeply followed our previous work: spectral data preprocessing, one-dimensional data processing, two-dimensional spectral imaging data processing and methods optimization for different observation mode data. The major contents include spectral flat field correction, geometric correction, frequency shift, improvement of SNR, measurement and correction of asymmetric instrument profile, improvement of spatial resolution of spectral imaging, and so on. The characteristics and innovations of this proposal include the establishment of spectral synthesis flat field by items separation method, the improvement of signal - to - noise ratio by the Principal Component Analysis, and the reconstruction of two dimensional monochromatic image with synchronization image of photosphere. The research can not only be applied directly to the NVST spectrometers, but also provide reference for the future data processing of large-scale solar observation equipment.