论文标题
h的超精细激发h $^+$
Hyperfine excitation of SH$^+$ by H
论文作者
论文摘要
Sh $^+$是漫射星际云中出奇的广泛分子离子。在那里,它在触发硫化学的角色中起着重要的作用。此外,在密集的分子云,\ mbox {所谓的}散落区域(PDRS)和朝向高质量原始恒定的紫外线云的紫外线缩小边缘上检测到了Sh $^+$发射线。精确确定SH $^+$丰度和在这些能量环境中普遍存在的物理条件取决于知道SH $^+$分子与氢原子,氢分子和电子之间无弹性碰撞的速率系数。在本文中,我们得出了SH $^+$ - h细和超细分辨的速率系数,该系数是从SH $^+$ -H碰撞的最新量子计算中得出的,包括非弹性,交换和反应性过程。所使用的方法是基于无限级别的突然方法。在前31个罚款水平和61个超精细水平的Sh $^+$之间的州对国家速率系数在10到1000 k的温度中获得了SH $^+$。良好的结构分辨率系数呈现出强大的倾向规则,有利于$ΔJ=ΔN$过渡。 $ΔJ=ΔF$倾向规则是针对超精细转变的。 {新的速率系数将有助于从PDR和紫外线辐射的冲击中解释Sh $^+$光谱,在这些冲击中,在氢分子方面,丰富的氢原子具有很大的意义。
SH$^+$ is a surprisingly widespread molecular ion in diffuse interstellar clouds. There, it plays an important role triggering the sulfur chemistry. In addition, SH$^+$ emission lines have been detected at the UV-illuminated edges of dense molecular clouds, \mbox{so-called} photo-dissociation regions (PDRs), and toward high-mass protostars. An accurate determination of the SH$^+$ abundance and of the physical conditions prevailing in these energetic environments relies on knowing the rate coefficients of inelastic collisions between SH$^+$ molecules and hydrogen atoms, hydrogen molecules, and electrons. In this paper, we derive SH$^+$--H fine and hyperfine-resolved rate coefficients from the recent quantum calculations for the SH$^+$--H collisions, including inelastic, exchange and reactive processes. The method used is based on the infinite order sudden approach. State-to-state rate coefficients between the first 31 fine levels and 61 hyperfine levels of SH$^+$ were obtained for temperatures ranging from 10 to 1000 K. Fine structure-resolved rate coefficients present a strong propensity rule in favour of $Δj = ΔN$ transitions. The $Δj = ΔF$ propensity rule is observed for the hyperfine transitions. {The new rate coefficients will help significantly in the interpretation of SH$^+$ spectra from PDRs and UV-irradiated shocks where the abundance of hydrogen atoms with respect to hydrogen molecules can be significant.