论文标题
在形成原星磁盘期间的化学演化
Chemical evolution during the formation of a protoplanetary disk
论文作者
论文摘要
（删节）这项研究的目的是研究从质子相到形成磁盘形成的化学演化，并确定冷和密集核对磁盘最终组成的影响。我们使用自适应网状电流RAMSES代码进行了3D非理想的磁磁动力学（MHD）模拟。对于以幼旋旋转支持的磁盘结尾的每个粒子，我们使用三相气体元素化学代码Nautilus进行化学模拟。考虑了两种不同的初始丰度，这些含量是冷核的特征。将普通物种丰富的最终分布相互比较，以及冷核的最初丰度。我们发现分子的空间分布反映了它们对温度分布的敏感性。磁盘中化学元件的主要载体通常与冷核中的化学元素相同，除了S含S型物种，其中HS被H $ _2 $ _2 $ S $ _3 $和P-BAREARGER物种取代，而P-bareation物种会导致PO，PN，HCP和CP形成PO，PN，HCP和CP。但是，随着时间的流逝，丰富的物种的丰富性变化。对于“大型”复杂有机分子（COM）的情况，尤其是这种情况，例如Ch $ _3 $ CHO，CH $ _3 $ _3 $ NH $ _2 $，CH $ _3 $ _3 $ OCH $ _3 $和HCOOCH $ _3 $，这些$ _3 $看到它们的丰度在倒塌期间显着增加。尽管冷核中的丰度明显不同，但这些COM在磁盘中通常具有相似的丰富性。相反，许多自由基的丰富性随时间而减少。许多物种在冷核和磁盘中仍然显示出相同的丰度，这表明这些分子在冷核中有效形成。这包括h $ _2 $ o，h $ _2 $ co，hnco和“小” com，例如ch $ _3 $ oh，ch $ _3 $ cn和nh $ _2 $ cho。
(Abridged) The aim of this study is to investigate the chemical evolution from the prestellar phase to the formation of the disk, and to determine the impact that the chemical composition of the cold and dense core has on the final composition of the disk. We performed 3D nonideal magneto-hydrodynamic (MHD) simulations of a dense core collapse using the adaptive-mesh-refinement RAMSES code. For each particle ending in the young rotationally supported disk, we ran chemical simulations with the three-phase gas-grain chemistry code Nautilus. Two different sets of initial abundances, which are characteristic of cold cores, were considered. The final distributions of the abundances of common species were compared to each other, as well as with the initial abundances of the cold core. We find that the spatial distributions of molecules reflect their sensitivity to the temperature distribution. The main carriers of the chemical elements in the disk are usually the same as the ones in the cold core, except for the S-bearing species, where HS is replaced by H$_2$S$_3$, and the P-bearing species, where atomic P leads to the formation of PO, PN, HCP, and CP. However, the abundances of less abundant species change over time. This is especially the case for "large" complex organic molecules (COMs) such as CH$_3$CHO, CH$_3$NH$_2$, CH$_3$OCH$_3$, and HCOOCH$_3$ which see their abundances significantly increase during the collapse. These COMs often present similar abundances in the disk despite significantly different abundances in the cold core. In contrast, the abundances of many radicals decrease with time. A significant number of species still show the same abundances in the cold core and the disk, which indicates efficient formation of these molecules in the cold core. This includes H$_2$O, H$_2$CO, HNCO, and "small" COMs such as CH$_3$OH, CH$_3$CN, and NH$_2$CHO.
