Calculation of rate coefficients for the excitation of rotational energy levels of the H2CS molecule by collisions with He atoms

通过与 He 原子碰撞激发 H2CS 分子旋转能级的速率系数的计算

• 批准号: 262982349
• 负责人: Professor Dr. Wilhelm H. Kegel (†)
• 金额: --
• 依托单位: Zentrum für Astronomie und Astrophysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/262982349?language=en
• 关键词: Calculation; rate; coefficients; excitation; rotational

The H2CS molecule has been observed in many interstellar clouds as well as in the circumstellar envelope of the carbon star IRC+10216. For a quantitative interpretation of the observed data one has to perform NLTE radiative transfer calculations. For such calculations one needs to know the frequencies and the transitionprobabilities of many (also non-observed) spectral lines as well as the rate coefficients for excitation and deexcitation by collisions. The goal of the present project is to calculate rate coefficients for collisions between H2CS molecules and He atoms. In interstellar space collisional excitation is dominated by collisions with H2 molecules. These may be approximated reasonably well by collisions with He atoms. The latter are easier to calculate.

在许多星际云以及碳恒星IRC+10216的室内包膜中都观察到了H2CS分子。要对观察到的数据进行定量解释，必须执行NLTE辐射转移计算。为了进行此类计算，人们需要了解许多（也是非观察到）光谱线的频率和过渡性，以及碰撞引起激发和消除的速率系数。本项目的目的是计算H2CS分子和HE原子之间碰撞的速率系数。在星际空间中，碰撞激发主要由与H2分子的碰撞。通过与He原子发生冲突，可以很好地近似这些。后者更容易计算。