1999/06/03 by N. Katz, I. Furman, O. Biham +2 · 11 citations
Chemistry · Physics and Astronomy · #Astrophysics and Star Formation Studies #Desorption #Diffusion #Fullerene Chemistry and Applications #Hydrogen #Hydrogen atom #Hydrogen molecule #Interstellar medium #Kinetic energy #Quantum, superfluid, helium dynamics #Range (aeronautics) #Sticking probability #astro-ph #physics.chem-ph
paper · pdf · doi:10.1086/307642
published as Astrophys.J. 522 (1999) 305 · 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 http://dumbo.fiz.huji.ac.il/users/itayf/abs04.html To be published in Astro. Phys. J., vol. 522/#2, Sept. 10 1999
arxiv created 1999/06/03 · openalex publication_date 1999/09/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
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 best fit 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.