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arXiv · 1202.0494

Color Gradients in Galaxies Out to z~3: Dependence on Galaxy Properties

Niraj Welikala·Jean-Paul Kneib
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Abstract

Using HST/ACS observations, we measure the color gradients of 3248 galaxies in the GOODS-South field out to z~3 and i_{AB}<25.5 and characterize their dependence on galaxy properties (luminosity, apparent magnitude, galaxy size, redshift and morphological type). The color gradient is measured by the difference of v-i color outside (R_{50} 1, galaxies show increasingly bluer cores while the color of the outskirts does not change as rapidly. At z~2.5 and -22.0 =2 is concentrated in their central regions. These color gradients and their dependence on galaxy properties could also have a significant impact on shear measurements in upcoming weak lensing cosmological surveys.

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Niraj Welikala, Jean-Paul Kneib. 2012-02-02. Color Gradients in Galaxies Out to z~3: Dependence on Galaxy Properties. https://arxiv.org/abs/1202.0494

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