Photometric metallicity of the galactic halo based on SCUSS and SDSS

doi:10.7523/j.issn.2095-6134.2018.04.007

Abstract

Abstract: Based on the correlation between[Fe/H] of F-/G-type main-sequence star and color index, we simulate the distribution of metallicity of the halo star using Monte-Carlo method based on u-g and g-r from SCUSS and SDSS. We select F-/G-type main-sequence star in halo as tracer and study the sample in the Z<-10 kpc,Z<-12 kpc, and Z<-15 kpc intervals, where Z represents the distance of the star from the galactic plane. The metallicity distribution of selected stars in every interval can be fitted by three-Gaussian model, with peaks at[Fe/H]~-0.60,-1.55, and -2.20. Based on our analysis, we find that the two components with metal-poor peaks are associated with the inner and outer halo and the metal-rich component is contributed by substructure in the halo.

Key words: galactic halo, metallicity, galactic structure

CLC Number:

P156.5

ZUO Wenbo, DU Cuihua. Photometric metallicity of the galactic halo based on SCUSS and SDSS[J]. , 2018, 35(4): 468-472.

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