High-α-Metal-Rich stars in the LAMOST-MRS survey and its connection with the galactic bulge

作     者：Hao-Peng Zhang Yu-Qin Chen Gang Zhao Jing-Kun Zhao Xi-Long Liang Hai-Ning Li Ya-Qian Wu Ali Luo Rui Wang Hao-Peng Zhang;Yu-Qin Chen;Gang Zhao;Jing-Kun Zhao;Xi-Long Liang;Hai-Ning Li;Ya-Qian Wu;Ali Luo;Rui Wang

作者机构：CAS Key Laboratory of Optical AstronomyNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space ScienceUniversity of Chinese Academy of SciencesBeijing 100049China 

出 版 物：《Research in Astronomy and Astrophysics》 (天文和天体物理学研究（英文版）)

年 卷 期：2021年第21卷第6期

页      面：424-432页

核心收录：

学科分类：07[理学] 070401[理学-天体物理] 0704[理学-天文学] 

基　　金：supported by the National Natural Science Foundation of China(Nos.11988101,11625313,11890694,11973048 and 11927804) the 2-m Chinese Space Survey Telescope project and the National Key R&D Program of China(No.2019YFA0405502) supported by the Astronomical Big Data Joint Research Center,co-founded by the National Astronomical Observatories,Chinese Academy of Sciences and the Alibaba Cloud 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 provided by the National Development and Reform Commission 

主　　题：stars:late type stars:abundances stars:fundamental parameters Galaxy:disk Galaxy:evolution Galaxy:structure 

摘      要：We report the detection of a large sample of high-α-metal-rich stars on the low giant branch with 2.60.2 than the comparison *** properties strongly indicate its connection with the outer bar/bulge region at R=3-5 kpc.A tentative interpretation of this special group is that its stars were formed in the X-shaped bar/bulge region,close to its corotation radius,where radial migration is the most intense,and brings them to present locations at 9 kpc and *** eccentricities and slightly outward radial excursions of its stars are consistent with this *** kinematics(cold)and chemistry([α/Fe]~0.1)further support the formation of the instability-driven X-shaped bar/bulge from the thin disk.