Color gradients of spiral disks in the Sloan Digital Sky Survey
Color gradients of spiral disks in the Sloan Digital Sky Survey
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DOI：
10.1088/1674-4527/9/10/004
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发表时间：
2009-05
影响因子：
1.8
通讯作者：
Chien-Liang Liu;S. Shen;Z. Shao;R. Chang;J. Hou;J. Yin;D. Yang
中科院分区：
文献类型：
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作者：
Chien-Liang Liu;S. Shen;Z. Shao;R. Chang;J. Hou;J. Yin;D. Yang
我们从斯隆数字巡天（SDSS-DR4）的第四次数据发布中选择了约20,000个面朝螺旋星系的样本，研究了星系盘的径向颜色梯度。我们将具有相似浓度、大小和光度的星系组合起来，构建复合星系，然后通过叠加所有成员星系的方位平均径向颜色轮廓来测量它们的颜色轮廓。除了最小的星系（r503 kpc）外，几乎所有星系都呈现负的盘色梯度，平均g−R梯度为kpc−1，R−z梯度为kpc−1。星系盘的颜色梯度与星系的形态类型无关，与星系盘表面亮度μ d密切相关，表面亮度越低的星系盘颜色梯度越陡。我们将颜色梯度和表面亮度之间的内在相关性量化为G gr = - 0。011 μ d + 0。233和grz =−0。015 μ d + 0。324年。这些量化的相关性为螺旋星系的形成和演化模型提供了严格的观测约束。
We investigate the radial color gradients of galactic disks using a sample of ~ 20 000 face-on spiral galaxies selected from the fourth data release of the Sloan Digital Sky Survey (SDSS-DR4).We combine galaxies with similar concentrations, sizes and luminosities to construct composite galaxies, and then measure their color profiles by stacking the azimuthally averaged radial color profiles of all the member galaxies. Except for the smallest galaxies ( R 50 3 kpc), almost all galaxies show negative disk color gradients with mean g − r gradient mag kpc − 1 and r − z gradient mag kpc − 1 . The disk color gradients are independent of the morphological types of galaxies and strongly dependent on the disk surface brightness μ d , with lower surface brightness galactic disks having steeper color gradients.We quantify the intrinsic correlation between color gradients and surface brightness as G gr = − 0 . 011 μ d + 0 . 233 and G rz = − 0 . 015 μ d + 0 . 324 . These quantified correlations provide tight observational constraints on the formation and evolution models of spiral galaxies.