Publication Abstracts

Langer and Glassgold 1976

Langer, W.D., and A.E. Glassgold, 1976: Time scales for molecule formation by ion-molecule reactions. Astron. Astrophys., 48, 395-403.

Analytical solutions are obtained for nonlinear differential equations governing the time-dependence of molecular abundances in interstellar clouds. Three gas-phase reaction schemes are considered separately for the regions where each dominates. The particular case of CO, and closely related members of the Oh and CH families of molecules, is studied for given values of temperature, density, and the radiation field. Nonlinear effects and couplings with particular ions are found to be important. The time scales for CO formation range from 105 to a few ×106 years, depending on the chemistry and regime. The time required for essentially complete conversion of C+ to CO in the region where the H3+ chemistry dominates is several million years. Because this time is longer than or comparable to dynamical time scales for dense interstellar clouds, steady-state abundances may not be observed in such clouds.

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BibTeX Citation

@article{la00200p,
  author={Langer, W. D. and Glassgold, A. E.},
  title={Time scales for molecule formation by ion-molecule reactions},
  year={1976},
  journal={Astron. Astrophys.},
  volume={48},
  pages={395--403},
}

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RIS Citation

TY  - JOUR
ID  - la00200p
AU  - Langer, W. D.
AU  - Glassgold, A. E.
PY  - 1976
TI  - Time scales for molecule formation by ion-molecule reactions
JA  - Astron. Astrophys.
VL  - 48
SP  - 395
EP  - 403
ER  -

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