标题： 星系中尘埃-金属比的演化 显示英文标题

标题： Evolution of Dust-to-Metal Ratio in Galaxies

摘要： 本文基于一个包含冷吸积的金属和尘埃量的简单演化模型，研究了星系中尘埃-金属比随时间的演化。 我们考虑了恒星质量损失气体中的尘埃形成、冷密云中金属原子吸积导致的尘埃增长以及超新星激波引起的尘埃破坏。 特别是，我们提出吸积效率与恒星形成历史无关。 这在金属丰度（$Z$）-尘埃-气体比（$\cal D$）平面上预测了依赖于恒星形成历史的各种演化轨迹。 在这个框架下，附近漩涡星系线性关系（$Z$-$\cal D$）可以解释为一个恒定星系年龄序列。 我们强调，在$z\sim 1$处星系的$Z$-$\cal D$关系的观测研究对于限制尘埃生长和破坏效率非常有用。 我们还建议，处于$z\sim 3$的莱曼破缺星系具有非常低的尘埃与金属丰度比，通常为$\ltsim 0.1$。 尽管吸积效应对$Z$–$\cal D$平面上的演化轨迹影响很小，但吸积率的离散性可能会干扰与恒星年龄恒定的$Z$–$\cal D$关系。 显示英文摘要

摘要： This paper investigates the evolution of the dust-to-metal ratio in galaxies based on a simple evolution model for the amount of metal and dust with infall. We take into account grain formation in stellar mass-loss gas, grain growth by the accretion of metallic atoms in a cold dense cloud, and grain destruction by SNe shocks. Especially, we propose that the accretion efficiency is independent of the star-formation history. This predicts various evolutionary tracks in the metallicity ($Z$)--dust-to-gas ratio ($\cal D$) plane depending on the star-formation history. In this framework, the observed linear $Z$--$\cal D$ relation of nearby spiral galaxies can be interpreted as a sequence of a constant galactic age. We emphasize that an observational study of the $Z$--$\cal D$ relation of galaxies at $z\sim 1$ is very useful to constrain the efficiencies of dust growth and destruction. We also suggest that the Lyman break galaxies at $z\sim 3$ have a very low dust-to-metal ratio, typically $\ltsim 0.1$. Although the effect of infall on the evolutionary tracks in the $Z$--$\cal D$ plane is quite small, the dispersion of the infall rate can disturb the $Z$--$\cal D$ relation with a constant galactic age.