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arXiv · 2305.03311

A Catalog of Distance Determinations for the LAMOST DR8 K Giants in the Galactic Halo

Lan Zhang·Xiang-Xiang Xue·Chengqun Yang·Feilu Wang·Hans-Walter Rix·Gang Zhao·Chao Liu
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Abstract

We present a catalog of distances for 19544 K giants drawn from LAMOST DR8. Most of them are located in the halo of the Milky Way up to ~120~kpc. There are 15% K giants without SDSS photometry, for which we supplements with Pan-STARRS1 (PS1) photometry calibrated to SDSS photometric system. The possible contamination of the red clumps/horizontal branch are removed according to metallicities and colors before the distance determination. Combining the LAMOST spectroscopic metallicities with the SDSS/PS1 photometry, we estimate the absolute magnitudes in SDSS $r-$band, the distance moduli, and the corresponding uncertainties through an Bayesian approach devised by Xue et al. (2014) for the SEGUE halo K-giants. The typical distance precision is about 11%. The stars in the catalog lie in a region of 4-126 kpc from the Galactic center, of which with 6, 320 stars beyond 20 kpc and 273 stars beyond 50 kpc, forming the largest spectroscopic sample of distant tracers in the Milky Way halo so far.

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Lan Zhang, Xiang-Xiang Xue, Chengqun Yang, Feilu Wang, Hans-Walter Rix, Gang Zhao, Chao Liu. 2023-05-05. A Catalog of Distance Determinations for the LAMOST DR8 K Giants in the Galactic Halo. https://doi.org/10.3847/1538-3881%2Facc9bb

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