Should we believe the results of ultraviolet–millimetre galaxy spectral energy distribution modelling?
Should we believe the results of ultraviolet–millimetre galaxy spectral energy distribution modelling?
复制标题
我们应该相信紫外毫米星系光谱能量分布模型的结果吗？
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
Daniel J B Smith
中科院分区：
文献类型：
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作者：
C. Hayward;Daniel J B Smith
星系光谱能量分布（SED）建模是一种强大的工具，但由于通常无法获得独立的确定值，因此很难限制它能够推断出星系属性（例如恒星形成率，SFR）的真实值。然而，星系模拟可以提供一种测试SED建模技术的方法。在这里，我们提出了一个数值实验，我们将SED建模代码MAGPHYS应用于通过执行三维尘埃辐射转移对孤立盘状星系和主要星系合并的流体动力学模拟产生的紫外(UV) -毫米（mm）合成光度。我们将SED模型推断的性质与真实值进行了比较，发现MAGPHYS可以很好地恢复模拟星系的大部分物理参数。特别是，它恢复一致的参数与视角无关，即使每个视角和时间步长都是独立建模的，模拟的相邻时间步长也会产生平滑变化的结果。当我们在辐射传输计算中使用smc型本征粉尘消光曲线时，这一规则的显著例外发生。在这种情况下，MAGPHYS使用的双组分尘埃模型无法有效地校正模拟星系的衰减，从而导致潜在的重大误差（尽管我们在这种情况下只能获得勉强可以接受的拟合）。总的来说，我们的结果让我们对SED模型推断星系物理性质的能力充满信心，尽管有一些警告。
Galaxy spectral energy distribution (SED) modelling is a powerful tool, but constraining how well it is able to infer the true values for galaxy properties (e.g. the star formation rate, SFR) is difficult because independent determinations are often n ot available. However, galaxy simulations can provide a means of testing SED modelling techniques. Here, we present a numerical experiment in which we apply the SED modelling code MAGPHYS to ultraviolet (UV)‐ millimetre (mm) synthetic photometry generated from hydrodynamical simulations of an isolated disc galaxy and a major galaxy merger by performing three-dimensional dust radiative transfer. We compare the properties inferred from the SED modelling with the true values and find that MAGPHYS recovers most physical parameters of the simulated galaxies well. In particular, it recovers consistent parameters irrespecti ve of the viewing angle, with smoothly varying results for neighbouring time steps of the simulati on, even though each viewing angle and time step is modelled independently. The notable exception to this rule occurs when we use an SMC-type intrinsic dust extinction curve in the radiative transfer calculations. In this case, the two-component dust model used by MAGPHYS is unable to effectively correct for the attenuation of the simulated galaxies, which leads to potentially significant errors (although we obtain only marginally acceptable fits in this case). Over all, our results give confidence in the ability of SED modelling to infer physical properties of galaxies, albeit with some caveats.
影响因子：
3.5
作者：
S. Eales;L. Dunne;D. Clements;A. Cooray;G. Zotti;S. Dye;R. Ivison;M. Jarvis;G. Lagache
通讯作者：
S. Eales;L. Dunne;D. Clements;A. Cooray;G. Zotti;S. Dye;R. Ivison;M. Jarvis;G. Lagache