Study on the Classification of LAMOST Early Stellar Spectrum Template by Mahalanobis Distance
CHEN Shu-xin 1, 2, SUN Wei-min1*, SONG Yi-han3
1. Key Lab of In-fiber Integrated Optics, Ministry of Education, Harbin Engineering University, Harbin 150001, China
2. College of Mechanical and Electrical Engineering, Qiqihar University, Qiqihar 161006, China
3. Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China
Abstract：With the continuous accumulation of astronomical data, Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST) has completed six years of large-scale sky surveys. The DR5 dataset has obtained more than 9 million spectrum data, including early-type stellar spectra with the lower observation proportion. The correct stellar classification template library can improve the classification accuracy. The currently used classification templates in LAMOST pipeline which don’t completely cover all the subtypes such as B-type stars, because they were constructed using DR1 data without enough early type stars. In this paper, the B-type stellar spectra in LAMOST DR5 have been collected as our research object, and the reference B-type spectra are from the library of ELODIE. Firstly, we complete the correlation analysis of 37 spectra of ELODIE B-type stars. After removing three weakly correlated spectra, 34 spectra of ELODIE B-type stars spectra were selected as the cluster center. The majority of the published LAMOST DR5 labels were marked as B6 (7662) and B9 (3969) and spectra were measured by Mahalanobis distances, with the supervised clustering, 34 LAMOST early-type stellar spectral data were marked as 13 subtypes according to ELODIE labels covering from B2 to B9 subclasses. The intra-class distance of each spectral subtype is determined by linear analysis to ensure that the wavelength coverage and resolution are completely consistent with the LAMOST data. The average spectral line of the corresponding subclass is calculated removing the outliers, thus 13 subtype spectral classification templates of B-type stars provide a good reference for later template completion.
陈淑鑫，孙伟民，宋轶晗. 马氏距离度量LAMOST早型星光谱的分类研究[J]. 光谱学与光谱分析, 2019, 39(05): 1618-1622.
CHEN Shu-xin, SUN Wei-min, SONG Yi-han. Study on the Classification of LAMOST Early Stellar Spectrum Template by Mahalanobis Distance. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2019, 39(05): 1618-1622.
