论文标题
了解CO在星体化学模型中的扩散的影响
Understanding the impact of diffusion of CO in the astrochemical models
论文作者
论文摘要
较轻的物种在星际粉尘晶粒表面的迁移率在通过复杂分子形成简单的情况下起着至关重要的作用。一氧化碳是最丰富的分子之一，其表面扩散在形成许多分子中至关重要。最近的实验室实验发现，在晶粒表面的CO的扩散屏障范围不同，它们的使用可以显着影响几个分子的丰度。在天体化学模型中，研究了CO的不同扩散屏障的影响，以了解其对固体CO的影响以及其作为反应伴侣的物种。气体网络用于三种不同的物理条件。冷核和热身模型，速度缓慢和快速加热。所有物种都使用扩散和解吸屏障之间的两个不同的比率（0.3和0.5）。对于每种物理条件和比率，对于最低扩散屏障的模型，六个不同的模型通过Co。SoldCo丰度的扩散屏障的产生少于0.1％的水冰，对于冷云而言，对于缓慢而快速的热身模型，最大的水冰的产量低于0.1％。同样，固体co $ _2 $浓缩云的生产过量（占水的140％）。 h $ _2 $ co和ch $ _3 $ oh的丰富度显示出相反的趋势，hcooh，ch $ _3 $ cho，nh $ _2 $ co和ch $ _3 $ _3 $ coch $ _3 $的生产量较低，用于较低的模型，而在多种模型之间，具有相当大的差异障碍物的差异很大，并且具有相当多的差异。与具有较低扩散屏障的模型相比，具有较高扩散屏障的模型与观察到的丰度相对更好。
The mobility of lighter species on the surface of interstellar dust grains plays a crucial role in forming simple through complex molecules. Carbon monoxide is one of the most abundant molecules, its surface diffusion on the grain surface is essential to forming many molecules. Recent laboratory experiments found a diverse range of diffusion barriers for CO on the grain surface, their use can significantly impact the abundance of several molecules. The impact of different diffusion barriers of CO, in the astrochemical models, is studied to understand its effect on the abundance of solid CO and the species for which it is a reactant partner. A gas-grain network is used for three different physical conditions; cold-core and warm-up models with slow and fast heating rates. Two different ratios (0.3 and 0.5) between diffusion and desorption barrier are utilized for all the species. For each physical condition and ratio, six different models are run by varying diffusion barriers of CO. Solid CO abundance for the models with the lowest diffusion barrier yields less than 0.1% of water ice for cold clouds and a maximum of 0.4% for slow and fast warm-up models. Also, solid CO$_2$ in dense clouds is significantly overproduced (140 % of water). The abundance of H$_2$CO and CH$_3$OH showed an opposite trend, and HCOOH, CH$_3$CHO, NH$_2$CO, and CH$_3$COCH$_3$ are produced in lower quantities for models with low diffusion barriers for CO. Considerable variation in abundance is observed between models with the high and low diffusion barrier. Models with higher diffusion barriers provide a relatively better agreement with the observed abundances when compared with the models having lower diffusion barriers.
