Characteristic of Lunar Water Distribution, Using Solar Wind as a Possible Source

This is the authors' abstract. We don't add key points for this paper.

Recent observations confirmed that the lunar surface is hydrated. Former Monte-Carlo simulation has estimated the potential amount of water in the polar regions, whereas the distribution character of water in the lunar space environment remains unknown. By applying a combined model of Monte-Carlo method and a central force algorithm based on energy conservation, this paper has investigated the character of the water molecular density distribution in the Moon's exosphere and the evolution of global surficial density, using solar wind proton as the water origin. The results show about 4.12% of all water molecules travel down to the Permanently Shadowed Regions (PSR) and become stable, under the circumstance that the timescale for photo-dissociation is 64000 seconds for water, which agrees with the previous simulation. It also indicates there are larger abundances of water in higher latitude regions.