论文标题
源结构对复杂有机物排放的重要性III。圆盘周围的磁盘的影响
Importance of source structure on complex organics emission III. Effect of disks around massive protostars
论文作者
论文摘要
复杂的有机分子仅检测到高质量质子的一部分。这项工作的目的是研究高质量磁盘是否可以解释某些巨大的原始系统缺乏甲醇排放。我们考虑仅包膜和一个包膜加盘模型，并使用RADMC-3D计算甲醇发射。分别考虑了两个模型的高毫米和低毫米（mm）不透明度粉尘，并且甲醇丰度被参数化。由于磁盘中这些物体的高积聚速率，包括粘性加热。与低质量原恒星相反，磁盘的存在不会显着影响温度结构和甲醇的发射。磁盘的阴影效果对于高质量物体并不重要，由于粘性加热，磁盘中平面很热，由于高积聚速率，这是有效的。与对高质量原始物质的红外吸收线的观察一致，我们发现垂直温度反转，即磁盘中平面中的温度高于磁盘表面的温度，对于$ l = 10^4 $ l $ l $ $ _ {\ odot} $ _ {\ odot} $ and mmmmmm as y as o y as o o o的$ l = 10^4 $ l = 10^4 $ l = 10^4 $ l $ l = 10^4 $ l $ l = 550的模型。大量的质质体中观察到的大量观察到的甲醇发射中的散射可以大部分用较低的光度对象来解释，包括信封加上磁盘模型，包括低和高MM不透明度粉尘。具有或没有磁盘的模型无法解释甲醇对具有高亮度源的甲醇排放变化。但是，这些对象的$ l/m $表明它们可能与超紧张/超跨型HII区域有关。因此，可以用甲醇占没有甲醇的HII区域来解释甲醇对高光度源的低甲醇发射。
Complex organic molecules are only detected toward a fraction of high-mass protostars. The goal of this work is to investigate whether high-mass disks can explain the lack of methanol emission from some massive protostellar systems. We consider an envelope-only and an envelope-plus-disk model and use RADMC-3D to calculate the methanol emission. High and low millimeter (mm) opacity dust are considered for both models separately and the methanol abundance is parameterized. Viscous heating is included due to the high accretion rates of these objects in the disk. In contrast with low-mass protostars, the presence of a disk does not significantly affect the temperature structure and methanol emission. The shadowing effect of the disk is not as important for high-mass objects and the disk mid-plane is hot because of viscous heating, which is effective due to the high accretion rates. Consistent with observations of infrared absorption lines toward high-mass protostars, we find a vertical temperature inversion, i.e. higher temperatures in the disk mid-plane than the disk surface, at radii < 50au for the models with $L=10^4$ L$_{\odot}$ and large mm opacity dust as long as the envelope mass is >550 M$_{\odot}$. The large observed scatter in methanol emission from massive protostars can be mostly explained toward lower luminosity objects with the envelope-plus-disk models including low and high mm opacity dust. The methanol emission variation toward sources with high luminosities cannot be explained by models with or without a disk. However, the $L/M$ of these objects suggest that they could be associated with hypercompact/ultracompact HII regions. Therefore, the low methanol emission toward the high-luminosity sources can be explained by them hosting an HII region where methanol is absent.
