AVS 57th International Symposium & Exhibition
    Applied Surface Science Tuesday Sessions
       Session AS-TuP

Paper AS-TuP19
Sputtering of Lunar Regolith Simulant by Singly and Multicharged Constituents of the Solar Wind

Tuesday, October 19, 2010, 6:00 pm, Room Southwest Exhibit Hall

Session: Applied Surface Science Poster Session
Presenter: F.W. Meyer, Oak Ridge National Laboratory
Authors: F.W. Meyer, Oak Ridge National Laboratory
P.R. Harris, Oak Ridge National Laboratory
H.M. Meyer III, Oak Ridge National Laboratory
N. Barghouty, Marshall Space Flight Center NASA
J.H. Adams, Jr., Marshall Space Flight Center NASA
Correspondent: Click to Email
We report preliminary results on sputtering of a lunar regolith simulant sample by H+, Ar+, Ar6+ and Ar9+ at solar wind-relevant energies. Such interactions are an important determinant of lunar exosphere composition, and may provide a possible pathway leading to the production of water on the moon. The presence of lunar water was recently confirmed by a number of orbiting lunar missions. The ions are generated using an electron cyclotron resonance (ECR) ion source at source potentials between 10-15kV. After being extracted, transported, and decelerated, the ions are normally incident on a pressed lunar regolith simulant sample that is situated within a floating UHV scattering chamber. The relative bias between the ECR source and the surface end station was adjusted to produce a constant impact energy of 0.375keV/amu for each of the 4 ion beams investigated. To simulate the effect of the dominant proton component, which constitutes >90% of the solar wind, the lunar regolith simulant sample was prepared by exposure to a proton beam up to total fluences of ~2x1018 H+/cm2 prior to each of the Ar beam sputtering runs. Both transient and steady state conditions of sputtered species were monitored by a quadrupole mass spectrometer situated within the UHV scattering chamber. SEM and XPS analyses of the JSC-1A AGGL simulant were performed to monitor possible changes in surface morphology and composition during the pressing of the loose powder into the sample holder.