Erratum: The intrinsic shape of galaxies in SDSS/Galaxy Zoo
Erratum: The intrinsic shape of galaxies in SDSS/Galaxy Zoo
复制标题
DOI：
10.1093/mnras/stt1168
复制
发表时间：
2013-06
影响因子：
4.8
通讯作者：
S. Rodr'iguez;N. Padilla
中科院分区：
文献类型：
--
作者：
S. Rodr'iguez;N. Padilla
通过模拟SDSS DR8星系的轴比分布，我们发现了螺旋星系和椭圆形星系的本征3D形状。我们使用来自银河动物园项目的形态信息，并假设形状的内在非参数分布，同时考虑尘埃消光。我们测量了整个旋涡星系样本的尘埃消光，发现了一个比以前估计的更小的值，在SDSSr波段的边缘消光为$E_0=0.284^{+0.015}_{-0.026}$。我们还发现，长短轴比的分布平均值为0.267\pm 0.009美元，比以前的估计略大，这主要是因为采用了较低的消光率；同样的影响也影响了星系盘的圆度，其形状比以前的研究发现的要小，平均椭圆度为0.215\pm 0.013美元。对于椭圆星系，我们发现长短轴比的平均值为$0.584\pm 0.006$，这是由于去除了来自光度剖面的形态信息样本中存在的螺旋入侵者而导致的。当使用Galaxy Zoo数据选择椭圆形时，这些入侵者将被删除。我们发现星系的内部形状和它们的尘埃消光会随着绝对大小、颜色和物理大小的不同而变化。我们发现明亮的椭圆星系比暗的椭圆星系更球形，这一趋势也与星系的大小有关，并且椭圆星系的形状与颜色无关。对于螺旋星系，我们发现最红的星系像预期的那样有更高的尘埃消失率，这是因为这种变红主要是由于尘埃。我们还发现，盘的厚度随着光度和大小的增加而增加，更亮、更小、更红的星系的圆盘更少。
By modelling the axis ratio distribution of SDSS DR8 galaxies we find the intrinsic 3D shapes of spirals and ellipticals. We use morphological information from the Galaxy Zoo project and assume a non-parametric distribution intrinsic of shapes, while taking into account dust extinction. We measure the dust extinction of the full sample of spiral galaxies and find a smaller value than previous estimations, with an edge-on extinction of $E_0 = 0.284^{+0.015}_{-0.026}$ in the SDSS r band. We also find that the distribution of minor to major axis ratio has a mean value of $ 0.267 \pm 0.009 $, slightly larger than previous estimates mainly due to the lower extinction used; the same affects the circularity of galactic discs, which are found to be less round in shape than in previous studies, with a mean ellipticity of $0.215 \pm 0.013$. For elliptical galaxies, we find that the minor to major axis ratio, with a mean value of $0.584 \pm 0.006$, is larger than previous estimations due to the removal of spiral interlopers present in samples with morphological information from photometric profiles. These interlopers are removed when selecting ellipticals using Galaxy Zoo data. We find that the intrinsic shapes of galaxies and their dust extinction vary with absolute magnitude, colour and physical size. We find that bright elliptical galaxies are more spherical than faint ones, a trend that is also present with galaxy size, and that there is no dependence of elliptical galaxy shape with colour. For spiral galaxies we find that the reddest ones have higher dust extinction as expected, due to the fact that this reddening is mainly due to dust. We also find that the thickness of discs increases with luminosity and size, and that brighter, smaller and redder galaxies have less round discs.