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arXiv · 1810.12371

Vertical and radial metallicity gradients in high latitude galactic fields with SDSS

S. Tuncel Guctekin·S. Bilir·S. Karaali·O. Plevne·S. Ak
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Abstract

We used the ugr magnitudes of 1,437,467 F-G type main-sequence stars with metal abundance -2<[Fe/H]<+0.2 dex and estimated radial and vertical metallicity gradients for high Galactic-latitude fields (b>50) of the Milky Way Galaxy. The radial metallicity gradient d[Fe/H]/dR=-0.042(0.011) dex/kpc estimated for the stars with 1.31 5 kpc) in three R distance intervals, 6<R<=10, 10<R<=15 and 15<R<=20 kpc. The first one corresponding to the interval 6<R<=10 kpc is equal to d[Fe/H]/dz= -0.023(0.006) dex/kpc, while the others at larger R distances are close to zero. We derived synthetic vertical metallicity gradients for 2,230,167 stars and compared them with the observed ones. There is a good agreement between the two sets of vertical metallicity gradients for the thin disc, while they are different for the thick disc. For the halo, the conspicuous difference corresponds to the R distance interval 6<R<=10 kpc, while they are compatible at higher R distance intervals.

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S. Tuncel Guctekin, S. Bilir, S. Karaali, O. Plevne, S. Ak. 2018-10-29. Vertical and radial metallicity gradients in high latitude galactic fields with SDSS. https://doi.org/10.1016/j.asr.2018.10.041

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