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Syracuse University

TBD

2007

Articles 1 - 2 of 2

Full-Text Articles in Physics

Formation Of Molecular Hydrogen On Amorphous Silicate Surfaces, Gianfranco Vidali, Ling Li, E. Congiu, S. Swords Sep 2007

Formation Of Molecular Hydrogen On Amorphous Silicate Surfaces, Gianfranco Vidali, Ling Li, E. Congiu, S. Swords

Physics

Experimental results on the formation of molecular hydrogen on amorphous silicate surfaces are presented and analyzed using a rate equation model. The energy barriers for the relevant diffusion and desorption processes are obtained. They turn out to be significantly higher than those obtained for polycrystalline silicates, demonstrating the importance of grain morphology. Using these barriers we evaluate the efficiency of molecular hydrogen formation on amorphous silicate grains under interstellar conditions. It is found that unlike polycrystalline silicates, amorphous silicate grains are efficient catalysts of H_2 formation in diffuse interstellar clouds.


Molecular Hydrogen Formation On Amorphous Silicates Under Interstellar Conditions, Gianfranco Vidali, Hagai B. Perets, Ling Li, S. Swords, E. Congiu Apr 2007

Molecular Hydrogen Formation On Amorphous Silicates Under Interstellar Conditions, Gianfranco Vidali, Hagai B. Perets, Ling Li, S. Swords, E. Congiu

Physics

Experimental results on the formation of molecular hydrogen on amorphous silicate surfaces are presented for the first time and analyzed using a rate equation model. The energy barriers for the relevant diffusion and desorption processes are obtained. They turn out to be significantly higher than those obtained earlier for polycrystalline silicates, demonstrating the importance of grain morphology. Using these barriers we evaluate the efficiency of molecular hydrogen formation on amorphous silicate grains under interstellar conditions. It is found that unlike polycrystalline silicates, amorphous silicate grains are efficient catalysts of H_{2} formation within a temperature range which is relevant to ...