云南天文台抚仙湖太阳观测与研究基地的多波段光谱仪是一个中等分辨率的闪耀光栅光谱仪，用于精确测量太阳的磁场和速度场，可以同时观测三个波段的太阳可见光光谱。本研究课题的主要内容是基于IDL交互数据语言，利用多波段光谱仪在Hα和Ca II 8542 ?两个波段的初光光谱为多波段光谱仪设计一套适用的光谱数据预处理程序，并设计出一个图形用户界面。文中详细的介绍了平、暗场的获得，多波段光谱仪的数据预处理流程，包括数据的标准处理，有暗场处理，平场处理和波长定标，光谱中干涉条纹的抑制。 NVST多波段光谱数据的一个最大特点是，有非常严重的干涉条纹。通常对于干涉条纹的去除，通常采用Running Box法。但是，对于多波段光谱仪严重的干涉条纹，采用这种方法，会对光谱的分辨率，谱线的剩余强度产生严重破坏。因此，本科题针对Ca II 8542 ?和Hα两个通道中干涉条纹的特点，分别采用了插值拟合以及小波变换的方法重构出干涉条纹，并将其从经过标准处理后的数据中去除。同时，通过处理完的实验科学数据，对光谱仪的实际光谱分辨率和仪器轮廓做了估计，结果表明该光谱仪的实际分辨率符合最初的光学设计要求，并可以用其做进一步的科学研究。 经过验证，通过本处理过程，可以为研究者提供真实可靠的科学数据做进一步的科学分析。
其他摘要
The Multi-wavelength spectrometer of Fuxian Solar Observatory of Yunnan Astronomy Observatory is a moderate resolution grating spectrometer. It is(R ~ 130,000) designed for the accurate measurement of the velocity as well as magnetic field of the Sun.. It can observe three solar wavelength in the visible band. The main content of my master thesis is to design a data reduction package for the spectral data of the Multi-wavelength spectrometer, using the first-light of Hα channel and Ca II 8542 channel. And design a interative user interface to realize the data reduction processes. In this thesis, the acquisition of the background data and flat-field datathe background correction, flat-field correction and wavelength calibration is discussed in detail. It is also detailed discussed that the eliminate of interference fringes of the two channel, which is special for the Multi-wavelength spectrometer. The main characteristic of the Multi-wavelength spectrometer of the NVST is the strong interference fringes , especially in the Ca II 8542 channel. Generally, the Running Box is often used to eliminate the fringe in the spectral data in both the stellar spectrum and solar spectrum. But in our case, this method will reduce the spectral resolution and the deep of absorption line. So different methods are used to extract the fringe information from the Ca II 8542 channel and the Hα channel. Then the extracted fringe is subtract or divided from the flat-fielded data. In this thesis, the real spectral resolution and instrument profile are estimated using the experimental scientific data. The results indicate that this spectrograph, together with the subsequently data reduction routines, presently fulfills its optical design and is ready for further scientific observation. After the reduction processes, it is confirm that the reduced data is reliable for the further scientific analysis.
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