收稿日期: 2015-05-11
修回日期: 2015-05-27
网络出版日期: 2016-03-15
基金资助
国家自然科学基金委员会－中国科学院天文联合基金(U1231113)资助
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
顾加银 , 杜翠花 . SCUSS测光金属丰度定标及南银冠人马座星流的金属丰度估计[J]. 中国科学院大学学报, 2016 , 33(2) : 150 -154 . DOI: 10.7523/j.issn.2095-6134.2016.02.002
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
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