Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-03-11
Astrophys.J.661:L163-L166,2007
Astronomy and Astrophysics
Astrophysics
5 pages, 3 figures, 1 table. Accepted to ApJL. Shortened a bit
Scientific paper
10.1086/518862
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 diffuse interstellar clouds. The results also indicate that the hydrogen molecules are thermalized with the surface and desorb with low kinetic energy. Thus, they are unlikely to occupy highly excited states.
Biham Ofer
Brucato John Robert
Congiu Emanuele
Lederhendler Adina
Li Ling
No associations
LandOfFree
Molecular Hydrogen Formation on Amorphous Silicates Under Interstellar Conditions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Molecular Hydrogen Formation on Amorphous Silicates Under Interstellar Conditions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Molecular Hydrogen Formation on Amorphous Silicates Under Interstellar Conditions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-45457