A catalog of early-type emission-line stars and Hα line profiles from LAMOST DR2  

作　　者：Wen Hou A-Li Luo Jing-Yao Hu Hai-Feng Yang Chang-De Du Chao Liu Chien-De Lee Chien-Cheng Lin Yue-Fei Wang Yong Zhang Zi-Huang Cao Yong-Hui Hou 

机构地区：[1]Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China [2]University of Chinese Academy of Sciences, Beijing 100049, China [3]School of Computer Science and Technology, Taiyuan University of Science and Technology, Taiyuan 030024, China [4]Institute of Astronomy, National Central University, Jhongli [5]Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China [6]Nanjing Institute of Astronomical Optics & Technology, National Astronomical Observatories, Chinese Academy of Sciences, Nanjing 210042, China

出　　处：《Research in Astronomy and Astrophysics》2016年第9期39-50,共12页天文和天体物理学研究（英文版）

基　　金：supported by the National Key Basic Research Program of China (Grant No. 2014CB845700);the National Natural Science Foundation of China (Grant Nos. 11390371 and 11233004);The Guo Shou Jing Telescope (the Large Sky Area Multi-Object Fiber Spectroscopic Telescope, LAMOST) is a National Major Scientific Project built by the Chinese Academy of Sciences. Funding for the project has been provided by the National Development and Reform Commission

摘　　要：We present a catalog including 11 204 spectra of 10436 early-type emission-line stars from LAMOST DR2, among which 9752 early-type emission-line spectra are newly discovered. For these early- type emissionqine stars, we discuss the morphological and physical properties of their low-resolution spectra. In this spectral sample, the Hα emission profiles display a wide variety of shapes. Based on the Hα line profiles, these spectra are categorized into five distinct classes： single-peak emission, single-peak emission in absorption, double-peak emission, double-peak emission in absorption, and P-Cygni profiles. To better understand what causes the Hc~ line profiles, we divide these objects into four types from the perspective of physical classification, which include classical Be stars, Herbig Ae/Be stars, close binaries and spectra contaminated by H n regions. The majority of Herbig Ae/Be stars and classical Be stars are identified and separated using a （H-K, K-W1） color-color diagram. We also discuss 31 binary systems that are listed in the SIMBAD on-line catalog and identify 3600 spectra contaminated by HⅡ regions after cross-matching with positions in the Dubout-Crillon catalog. A statistical analysis of line profiles versus classifications is then conducted in order to understand the distribution of Hc~ profiles for each type in our sample. Finally, we also provide a table of 172 spectra with Fen emission lines and roughly calculate stellar wind velocities for seven spectra with P-Cygni profiles.We present a catalog including 11 204 spectra of 10436 early-type emission-line stars from LAMOST DR2, among which 9752 early-type emission-line spectra are newly discovered. For these early- type emissionqine stars, we discuss the morphological and physical properties of their low-resolution spectra. In this spectral sample, the Hα emission profiles display a wide variety of shapes. Based on the Hα line profiles, these spectra are categorized into five distinct classes： single-peak emission, single-peak emission in absorption, double-peak emission, double-peak emission in absorption, and P-Cygni profiles. To better understand what causes the Hc~ line profiles, we divide these objects into four types from the perspective of physical classification, which include classical Be stars, Herbig Ae/Be stars, close binaries and spectra contaminated by H n regions. The majority of Herbig Ae/Be stars and classical Be stars are identified and separated using a （H-K, K-W1） color-color diagram. We also discuss 31 binary systems that are listed in the SIMBAD on-line catalog and identify 3600 spectra contaminated by HⅡ regions after cross-matching with positions in the Dubout-Crillon catalog. A statistical analysis of line profiles versus classifications is then conducted in order to understand the distribution of Hc~ profiles for each type in our sample. Finally, we also provide a table of 172 spectra with Fen emission lines and roughly calculate stellar wind velocities for seven spectra with P-Cygni profiles.

关 键 词：STARS early-type - stars emission-line  Be -- stars pre-main sequence -- binaries close 

分 类 号：P152[天文地球—天文学]