The distribution of interstellar dust in CALIFA edge-on galaxies via oligochromatic radiative transfer fitting
The distribution of interstellar dust in CALIFA edge-on galaxies via oligochromatic radiative transfer fitting
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DOI：
10.1093/mnras/stu612
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发表时间：
2014-03
影响因子：
4.8
通讯作者：
G. D. Geyter;M. Baes;P. Camps;J. Fritz;I. D. Looze;T. Hughes;S. Viaene;G. Gentile
中科院分区：
文献类型：
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作者：
G. D. Geyter;M. Baes;P. Camps;J. Fritz;I. D. Looze;T. Hughes;S. Viaene;G. Gentile
我们调查的星际尘埃的量和空间分布在边缘上的螺旋星系，使用详细的辐射传输模型的均匀样本的12个星系从卡拉阿尔托遗产积分场区调查。我们的自动拟合程序，FITSKIRT，首先对人工数据进行验证。这是通过同时再现斯隆数字巡天g-、r-、i-和z-波段对一个玩具模型的观测来完成的，以便联合收割机将不同波段的信息结合起来。我们表明，这种组合，oligochromatic拟合有明显的优势，特别是对灰尘属性的限制，标准的单色拟合。我们的样本中的所有星系模型使用三个组件的模型，由一个双指数盘来描述恒星和尘埃盘，并使用Sersic配置文件来描述中央隆起。完整的模型包含19个自由参数，我们能够将所有这些参数约束到令人满意的精度水平，而无需人为干预或强边界条件。除了两个星系外，我们的模型可以准确地再现整个样本。我们发现，尘埃盘的延伸率约为75%，但只有恒星盘的一半高。在V波段的平均正面光学深度是0.76，在我们的样本中0.60的扩散是相当可观的，这表明一些螺旋星系即使在正面观察时也是相对不透明的。
We investigate the amount and spatial distribution of interstellar dust in edge-on spiral galaxies, using detailed radiative transfer modelling of a homogeneous sample of 12 galaxies selected from the Calar Alto Legacy Integral Field Area survey. Our automated fitting routine, FITSKIRT, was first validated against artificial data. This is done by simultaneously reproducing the Sloan Digital Sky Survey g-, r-, i- and z-band observations of a toy model in order to combine the information present in the different bands. We show that this combined, oligochromatic fitting has clear advantages over standard monochromatic fitting especially regarding constraints on the dust properties. We model all galaxies in our sample using a three-component model, consisting of a double-exponential disc to describe the stellar and dust discs and using a Sersic profile to describe the central bulge. The full model contains 19 free parameters, and we are able to constrain all these parameters to a satisfactory level of accuracy without human intervention or strong boundary conditions. Apart from two galaxies, the entire sample can be accurately reproduced by our model. We find that the dust disc is about 75 per cent more extended but only half as high as the stellar disc. The average face-on optical depth in the V band is 0.76 and the spread of 0.60 within our sample is quite substantial, which indicates that some spiral galaxies are relatively opaque even when seen face-on.