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arXiv · 2105.14049

Anomalous intensities in the infrared emission of CH$^+$ explained by quantum nuclear motion and electric dipole calculations

P. Bryan Changala·David A. Neufeld·Benjamin Godard
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Abstract

The unusual infrared emission patterns of CH$^+$, recently detected in the planetary nebula NGC 7027, are examined theoretically with high-accuracy rovibrational wavefunctions and $ab$ $initio$ dipole moment curves. The calculated transition dipole moments quantitatively reproduce the observed $J$-dependent intensity variation, which is ascribed to underlying centrifugal distortion-induced interference effects. We discuss the implications of this anomalous behavior for astrochemical modeling of CH$^+$ production and excitation, and provide a simple expression to estimate the magnitude of this effect for other light diatomic molecules with small dipole derivatives.

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P. Bryan Changala, David A. Neufeld, Benjamin Godard. 2021-05-28. Anomalous intensities in the infrared emission of CH$^+$ explained by quantum nuclear motion and electric dipole calculations. https://doi.org/10.3847/1538-4357%2Fac05c8

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