论文标题
再现宇宙:鹰模拟与附近的尘埃式星系样品之间的比较
Reproducing the Universe: a comparison between the EAGLE simulations and the nearby DustPedia galaxy sample
论文作者
论文摘要
我们比较了低红移时模拟和观察到的星系的光谱能量分布(SED)和推断物理特性。我们利用使用辐射传输代码裙来得出的宇宙模拟的鹰套件的〜7000 z = 0星系的UV-Submillimetre模拟通量。我们将它们与附近星系的尘土样品样本中的UV-Submillimetre范围内的约800个观察到的星系进行了比较。为了获得全球属性,我们使用相同的约8000万款模型将SED拟合代码CIGALE一致地应用于两个数据集。该比较的结果表明,在SED和派生的物理特性中,模拟和观察之间的总体一致性以及许多差异。光学和远红外的制度以及基于全球发射,弥漫性尘埃和恒星质量的比例关系显示出很高的一致性。但是,与观测值相比,鹰星系的中红外通量被高估了,而远处的域则不够减弱。我们将这些差异归因于样品之间星系种群差异的组合,以及在Eagle-Skirt后期处理食谱中恒星形成区域的亚网格处理的局限性。我们的发现表明了详细的辐射转移计算和一致比较的重要性,并为改进的数值模型提供了建议。
We compare the spectral energy distributions (SEDs) and inferred physical properties for simulated and observed galaxies at low redshift. We exploit UV-submillimetre mock fluxes of ~7000 z=0 galaxies from the EAGLE suite of cosmological simulations, derived using the radiative transfer code SKIRT. We compare these to ~800 observed galaxies in the UV-submillimetre range, from the DustPedia sample of nearby galaxies. To derive global properties, we apply the SED fitting code CIGALE consistently to both data sets, using the same set of ~80 million models. The results of this comparison reveal overall agreement between the simulations and observations, both in the SEDs and in the derived physical properties, with a number of discrepancies. The optical and far-infrared regimes, and the scaling relations based upon the global emission, diffuse dust and stellar mass, show high levels of agreement. However, the mid-infrared fluxes of the EAGLE galaxies are overestimated while the far-UV domain is not attenuated enough, compared to the observations. We attribute these discrepancies to a combination of galaxy population differences between the samples, and limitations in the subgrid treatment of star-forming regions in the EAGLE-SKIRT post-processing recipe. Our findings show the importance of detailed radiative transfer calculations and consistent comparison, and provide suggestions for improved numerical models.