...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>PASJ: Publications of the Astronomical Society of Japan >A multi-transition study of molecules toward NGC 1068 based on high-resolution imaging observations with ALMA
【24h】

A multi-transition study of molecules toward NGC 1068 based on high-resolution imaging observations with ALMA

机译：基于ALMA高分辨率成像观察的NGC 1068分子的多跃迁研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We present 0.8-mm band molecular images and spectra obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) toward one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068. Distributions of CO isotopic species ((CO)-C-13 and (CO)-O-18) J = 3-2, CN N = 3-2, and CS J = 7-6 are observed toward the circumnuclear disk (CND) and a part of the starburst ring with an angular resolution of similar to 1''.3 x 1''.2. The physical properties of these molecules and shock-related molecules, such as HNCO, CH3CN, SO, and CH3OH, detected in the 3-mm band were estimated using rotation diagrams under the assumption of local thermodynamic equilibrium. The rotational temperatures of the CO isotopic species and the shock-related molecules in the CND are, respectively, 14-22 K and upper limits of 20-40 K. Although the column densities of the CO isotopic species in the CND are only from one-fifth to one-third of that in the starburst ring, those of the shock-related molecules are enhanced by a factor of 3-10 in the CND. We also discuss the chemistry of each species, and compare the fractional abundances in the CND and starburst ring with those of Galactic sources such as cold cores, hot cores, and shocked molecular clouds in order to study the overall characteristics. We find that the abundances of shock-related molecules are more similar to abundances in hot cores and/or shocked clouds than to cold cores. The CND hosts relatively complex molecules, which are often associated with shocked molecular clouds or hot cores. Because a high X-ray flux can dissociate these molecules, they must also reside in regions shielded from X-rays.
机译：我们向最近的具有活跃银河核（NGN 1068）的星系之一展示了用Atacama大毫米/亚毫米阵列（ALMA）获得的0.8毫米波段分子图像和光谱。CO同位素物种（（CO）- C-13和（CO）-O-18）朝着核周圆盘（CND）和星爆环的一部分带有一个圆弧，观察到J = 3-2，CN N = 3-2和CS J = 7-6。角分辨率类似于1''。3 x 1''。2在局部热力学平衡的假设下，使用旋转图估算了这些分子和与冲击有关的分子（如HNCO，CH3CN，SO和CH3OH）在3 mm波段内的物理性质。 CND中CO同位素物种和与冲击有关的分子的旋转温度分别为14-22 K和20-40 K的上限。尽管CND中CO同位素物种的柱密度仅来自一种在星爆环中的五分之一至三分之一，与冲击有关的分子在CND中增加了3-10倍。我们还讨论了每种物种的化学性质，并比较了CND和星爆环中的分数丰度与银河源（如冷核，热核和冲击分子云）的丰度，以研究总体特征。我们发现，与冲击有关的分子的丰度与热核和/或冲击云中的丰度比与冷核的丰度更相似。 CND包含相对复杂的分子，这些分子通常与震动的分子云或热核有关。因为高的X射线通量可以使这些分子解离，所以它们还必须位于不受X射线屏蔽的区域。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号