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arXiv · 1412.6628

LAMOST Spectroscopic Survey of the Galactic Anti-centre (LSS-GAC): target selection and the first release of value-added catalogues

Haibo Yuan·Xiaowei Liu·Zhiying Huo·Maosheng Xiang·Yang Huang·Bingqiu Chen·Huihua Zhang·Ningchen Sun·Chun Wang·Huawei Zhang·Yongheng Zhao·Ali Luo·Jianrong Shi·Guoping Li·Hailong Yuan·Yiqiao Dong·Guangwei Li·Yonghui Hou·Yong Zhang
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Abstract

As a major component of the LAMOST Galactic surveys, the LAMOST Spectroscopic Survey of the Galactic Anti-centre (LSS-GAC) aims to survey a significant volume of the Galactic thin/thick discs and halo for a contiguous sky area of over 3,400 deg$^2$ centred on the Galactic anti-centre ($|b| \leq 30^{\circ}$, $150 \leq l \leq 210^{\circ}$), and obtain $\lambda\lambda$3700 -- 9000 low resolution ($R \sim 1,800$) spectra for a statistically complete sample of $\sim 3$\,M stars of all colours down to a limiting magnitued of $r$ $\sim$ 17.8\,mag (to 18.5\,mag for limited fields). Together with Gaia, the LSS-GAC will yield a unique dataset to advance our understanding of the structure and assemblage history of the Galaxy, in particular its disk(s). In addition to the main survey, the LSS-GAC will also target hundreds of thousands objects in the vicinity fields of M\,31 and M\,33 and survey a significant fraction (over a million) of randomly selected very bright stars (VB; $r \le 14$ mag) in the northern hemisphere. During the Pilot and the first year Regular Surveys of LAMOST, a total of 1,042,586 [750,867] spectra of a signal to noise ratio S/N(7450\AA) $\ge$ 10 [S/N(4650\AA) $\ge$ 10] have been collected. In this paper, we present a detailed description of the target selection algorithm, survey design, observations and the first data release of value-added catalogues (including radial velocities, effective temperatures, surface gravities, metallicities, values of interstellar extinction, distances, proper motions and orbital parameters) of the LSS-GAC.

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Haibo Yuan, Xiaowei Liu, Zhiying Huo, Maosheng Xiang, Yang Huang, Bingqiu Chen, Huihua Zhang, Ningchen Sun, Chun Wang, Huawei Zhang, Yongheng Zhao, Ali Luo, Jianrong Shi, Guoping Li, Hailong Yuan, Yiqiao Dong, Guangwei Li, Yonghui Hou, Yong Zhang. 2014-12-20. LAMOST Spectroscopic Survey of the Galactic Anti-centre (LSS-GAC): target selection and the first release of value-added catalogues. https://doi.org/10.1093/mnras%2Fstu2723

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