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arXiv · 1802.06777

The selection function of the LAMOST Spectroscopic Survey of the Galactic Anticentre

B. -Q. Chen·X. -W. Liu·H. -B. Yuan·M. -S. Xiang·Y. Huang·C. Wang·H. -W. Zhang·Z. -J. Tian
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Abstract

We present a detailed analysis of the selection function of the LAMOST Spectroscopic Survey of the Galactic Anti-centre (LSS-GAC). LSS-GAC was designed to obtain low resolution optical spectra for a sample of more than 3 million stars in the Galactic anti-centre. The second release of value-added catalogues of the LSS-GAC (LSS-GAC DR2) contains stellar parameters, including radial velocity, atmospheric parameters, elemental abundances and absolute magnitudes deduced from 1.8 million spectra of 1.4 million unique stars targeted by the LSS-GAC between 2011 and 2014. For many studies using this database, such as those investigating the chemodynamical structure of the Milky Way, a detailed understanding of the selection function of the survey is indispensable. In this paper, we describe how the selection function of the LSS-GAC can be evaluated to sufficient detail and provide selection function corrections for all spectroscopic measurements with reliable parameters released in LSS-GAC DR2. The results, to be released as new entries in the LSS-GAC value-added catalogues, can be used to correct the selection effects of the catalogue for scientific studies of various purposes.

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B. -Q. Chen, X. -W. Liu, H. -B. Yuan, M. -S. Xiang, Y. Huang, C. Wang, H. -W. Zhang, Z. -J. Tian. 2018-02-19. The selection function of the LAMOST Spectroscopic Survey of the Galactic Anticentre. https://doi.org/10.1093/mnras%2Fsty454

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