一种海量光谱中类星体候选体红移测量与识别的算法  

Searching QSO Candidates and Calculating Their Redshfit from a Flood of Spectra

作　　者：宋轶晗[1,2,3] 罗阿理[1,2] 赵永恒[1,2] 

机构地区：[1]中国科学院国家天文台,北京100012 [2]中国科学院天文光学重点实验室,北京100012 [3]中国科学院研究生院,北京100049

出　　处：《光谱学与光谱分析》2011年第9期2578-2581,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(10973021)资助

摘　　要：提出一套对海量光谱中类星体的红移测的方法。类星体具有本身的宽发射线的特征,而以往光谱处理方法中,对于宽的发射线的识别存在不足之处。由于类星体的红移一般比较大,谱线移动的范围比较大,不易进行判定。所以本文针对类星体最重要的特征,利用低频点集方法,提取光谱中宽的发射线并与已知线表进行匹配,来获得类星体的红移并能够对类星体进行初步的识别。为提高谱线识别可靠性,文章还提出一种估计局部噪声的方法。该文的方法不依赖与光谱的流量定标,可以应用于无流量定标时的光谱,例如正在调试阶段的LAMOST光谱数据。In the present paper the author offers a method to search the QSO candidates and calculate their redshfit using their broad emission lines which are the most important character of quasars. It is hard to identify the lines in the quasar＇s spectra due to their redshihs distributing on a broad range. Spectra contain two components. One is continuum and the other is lines. The author uses a method of LFPS （low frequency points set） to build the continuum and detect the obvious emission lines, a method that can avoid the broad emission lines as a part of the continuum. The redshift can be calculated by comparing the extracted lines with the line table. The classification can be done with both emission lines and the redshift. For a better accurate rate to recog- nize the lines, this paper provides a method to estimate the level of the local noise. The method this paper used is independent of the flux calibration of the spectra. It can work for the spectra of the present LAMOST.

关 键 词：宽发射线 低频点集 标准差空间 线表匹配 

分 类 号：TP29[自动化与计算机技术—检测技术与自动化装置]