Document Type
Article
Date
6-3-1995
Keywords
TBD
Language
English
Disciplines
Physics
Description/Abstract
Recent experimental results about the formation of molecular hydrogen on astrophysically relevant surfaces under conditions close to those encountered in the interstellar medium are analyzed using rate equations. The parameters of the rate equation model are fitted to temperature-programmed desorption curves obtained in the laboratory. These parameters are the activation energy barriers for atomic hydrogen diffusion and desorption, the barrier for molecular hydrogen desorption, and the probability of spontaneous desorption of a hydrogen molecule upon recombination. The model is a generalization of the Polanyi-Wigner equation and provides a description of both first and second order kinetic processes within a single model. Using the values of the parameters that fit best the experimental results, the efficiency of hydrogen recombination on olivine and amorphous carbon surfaces is obtained for a range of hydrogen flux and surface temperature pertinent to a wide range of interstellar conditions.
Recommended Citation
Vidali, Gianfranco; Katz, N.; Furman, Itay; Biham, Ofer; and Pirronello, Valerio, "Molecular Hydrogen Formation on Astrophysically Relevant Surfaces" (1995). Physics - All Scholarship. 510.
https://surface.syr.edu/phy/510
Source
Harvested from Arxiv.org
Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.
Additional Information
18 pages of text, Latex. Figs. 1,2,7 in PS format, Figs. 3-6 in GIF format. Printing quality version of Figs. 3-6 is available at this http URL To be published in Astro. Phys. J., vol. 522/#2, Sept. 10 1999 More information at http://arxiv.org/abs/astro-ph/9906071