论文标题
使用$ν^2 $ GC半分析模型的星系中粒度分布的宇宙演变
Cosmic evolution of grain size distribution in galaxies using the $ν^2$GC semi-analytic model
论文作者
论文摘要
我们通过半分析星系形成模型（$ν^2 $ gc）研究了星际灰尘的宇宙学演化，重点是晶粒尺寸分布的演变。该模型预测了跨宇宙历史中星系中尘埃质量和晶粒尺寸分布的统计特性。我们确认该模型在当地宇宙中重现了尘埃气比与金属性之间的关系，并且类似银河系的晶粒大小分布（MW）类似样品与所谓的MRN分布相似，该分布重现了观察到的MW灭绝曲线。但是，我们的模型倾向于过度预测在红移$ z \ Lessim 0.8 $处的大量末端的灰尘质量功能，而它在较高的红移处重现了丰富的尘土飞扬的星系。我们还检查了晶粒尺寸分布与星系性能（金属性，特定的恒星形成速率，气体分数和恒星质量）之间的相关性，并观察到明显的大颗粒主导的，小谷物为主导的，小谷物的晶粒样分布，从未发展到演变阶段。结果，从未发展到进化的相位的灭绝曲线形状是平坦的，陡峭的和中间的（MW状的）。在固定的金属性下，晶粒尺寸的分布往往在较低的红移时具有较大的小晶粒。因此，灭绝曲线在较低的红移下倾向于陡峭。我们还预测，高红移处的超极性物体具有平坦的灭绝曲线，弱2175ÅBump强度。
We investigate the cosmological evolution of interstellar dust with a semi-analytical galaxy formation model ($ν^2$GC), focusing on the evolution of grain size distribution. The model predicts the statistical properties of dust mass and grain size distribution in galaxies across cosmic history. We confirm that the model reproduces the relation between dust-to-gas ratio and metallicity in the local Universe, and that the grain size distributions of the Milky Way (MW)-like sample become similar to the so-called MRN distribution that reproduces the observed MW extinction curve. Our model, however, tends to overpredict the dust mass function at the massive end at redshift $z\lesssim 0.8$ while it reproduces the abundance of dusty galaxies at higher redshifts. We also examine the correlation between grain size distribution and galaxy properties (metallicity, specific star formation rate, gas fraction, and stellar mass), and observe a clear trend of large-grain-dominated, small-grain-dominated, and MRN-like grain size distributions from unevolved to evolved stages. As a consequence, the extinction curve shapes are flat, steep, and intermediate (MW-like) from the unevolved to evolved phases. At a fixed metallicity, the grain size distribution tends to have larger fractions of small grains at lower redshift; accordingly, the extinction curve tends to be steeper at lower redshift. We also predict that supersolar-metallicity objects at high redshift have flat extinction curves with weak 2175 Åbump strength.
