论文标题
Illustristng和S2Cosmos:中性气体和灰尘演变的可能冲突
IllustrisTNG and S2COSMOS: possible conflicts in the evolution of neutral gas and dust
论文作者
论文摘要
我们通过i)在宇宙场的850UM上使用堆叠的亚毫米量通量来研究宇宙时间的银河尘埃质量的演变,而ii)ii)使用强大的后处理方法在宇宙学水动力学模拟的结果上使用可靠的后处理方法得出的尘埃质量。我们通过迫使模型和观测值在低红移时有效地对尘埃吸收系数进行自我校准,然后比较观测值与模型预测的演变。我们基于0 <z <0.5的Illustristng模拟创建尘埃质量函数(DMF),并将其与先前观察到的DMF进行比较。我们发现,从模拟得出的DMF中缺乏演变,与低红移DMF的经验得出的估计值相抵触。此外,我们观察到在红移范围0 <z <5上观察到的尘埃质量与星系恒星质量的平均比率的强劲演化,而即使将样品拆分为卫星和中心后,来自Illustristng的相应尘埃质量也显示出相对较小的演变。强烈观察到的进化与插图剂加后期处理所预测的弱进化之间的巨大差异可以通过在粉尘粒的性质中的强宇宙进化或模型中的局限性来解释。在后一种情况下,限制可能与以前的说法有关,即星系中的中性气体含量在Illustristng中的发展速度不够快。
We investigate the evolution in galactic dust mass over cosmic time through i) empirically derived dust masses using stacked submillimetre fluxes at 850um in the COSMOS field, and ii) dust masses derived using a robust post-processing method on the results from the cosmological hydrodynamical simulation IllustrisTNG. We effectively perform a self-calibration of the dust mass absorption coefficient by forcing the model and observations to agree at low redshift and then compare the evolution shown by the observations with that predicted by the model. We create dust mass functions (DMFs) based on the IllustrisTNG simulations from 0 < z < 0.5 and compare these with previously observed DMFs. We find a lack of evolution in the DMFs derived from the simulations, in conflict with the rapid evolution seen in empirically derived estimates of the low redshift DMF. Furthermore, we observe a strong evolution in the observed mean ratio of dust mass to stellar mass of galaxies over the redshift range 0 < z < 5, whereas the corresponding dust masses from IllustrisTNG show relatively little evolution, even after splitting the sample into satellites and centrals. The large discrepancy between the strong observed evolution and the weak evolution predicted by IllustrisTNG plus post-processing may be explained by either strong cosmic evolution in the properties of the dust grains or limitations in the model. In the latter case, the limitation may be connected to previous claims that the neutral gas content of galaxies does not evolve fast enough in IllustrisTNG.