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  • Open Access

Vibrational-excitation cross sections by electron impact on the CH radical for nonthermal plasmas

V. Laporta1,*, M. Telmini2, R. Ghosh3, and K. Chakrabarti4

  • *Contact author: vincenzo.laporta@cnr.it
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Phys. Rev. A 114, 022810 – Published 13 August, 2026

DOI: https://doi.org/10.1103/p5dr-pvtl

Abstract

Vibrational excitations of the CH molecule are critical for understanding the kinetics of the interstellar medium, stellar atmospheres, and plasma-assisted combustion. Building upon previous R-matrix calculations—which characterized the X2Π and a4Σ− electronic states of CH and the 1Σ+, 3Π, and 5Σ− resonant states of CH−—this study evaluates cross sections and rate coefficients for electron-impact vibrational excitation using the local complex potential method. State-to-state formalism is used to analyze electron-vibration energy exchange. Our results demonstrate that electron-driven processes provide non-negligible contributions to nonequilibrium kinetic modeling.

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Phys. Rev. A 114, 022810– Published 13 August, 2026
  • Received 25 March 2026
  • Accepted 28 July 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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