Journal of University of Chinese Academy of Sciences >
Photometric metallicity calibration based on SCUSS and metallicity estimates of Sagittarius stream in south Galactic cap
Received date: 2015-05-11
Revised date: 2015-05-27
Online published: 2016-03-15
Based on SDSS g,SDSS r,and SCUSS u photometry, we develop a photometric calibration for estimating the stellar metallicity from u－g and g－r colors by using the spectra of F- and G-type main-sequence stars. The rms scatter of the photometric metallicity residuals relative to spectrum-based metallicity is 0.14 dex when g－r<0.4, and 0.16 dex when g－r>0.4. Due to the deeper and more accurate magnitude of SCUSS u, we set the application of photometric metallicity estimation in the range of g<21. We select the Sagittarius (Sgr) stream stars in south Galactic cap to study metallicity distribution. We find that the Sgr stream at the cylindrical Galactocentric coordinates of R~19 kpc and |Z|~14 kpc exhibits a more metal-rich distribution than the halo.
Key words： metallicity; substructure; stellar content
GU Jiayin , DU Cuihua . Photometric metallicity calibration based on SCUSS and metallicity estimates of Sagittarius stream in south Galactic cap[J]. Journal of University of Chinese Academy of Sciences, 2016 , 33(2) : 150 -154 . DOI: 10.7523/j.issn.2095-6134.2016.02.002
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