SM31B-2497
Measurement of Energetic Neutral Atom Flux in the Lunar Exosphere using the LDEX Instrument

Wednesday, 16 December 2015
Poster Hall (Moscone South)
Jeffrey J Walker1, Jasper S Halekas2, Mihaly Horanyi3, Jamey Szalay3 and Andrew R Poppe4, (1)University of Iowa, Iowa City, IA, United States, (2)University of Iowa, Physics and Astronomy, Iowa City, IA, United States, (3)University of Colorado at Boulder, Physics, Boulder, CO, United States, (4)University of California Berkeley, Berkeley, CA, United States
Abstract:
Features of the LDEX data and collection properties of the LDEX instrument suggest that the integrated current signal comprises other sources in addition to dust grains.
In particular, the LDEX current is highly correlated with the solar wind flux, a puzzling issue because high energy ions should be excluded from the integrated signal.
One leading possibility is that energetic neutral atoms, produced by solar wind reflected from the moon's surface, are contributing to the signal, either through scattering from the LDEX target or through sputtering material from the target surface into the collector.
In this work, models for the contribution of energetic neutrals to the LDEX integrated current signal are evaluated.
Determining the LDEX current's dependency on energetic neutrals would allow a high signal-to-noise ratio measurement of energetic neutral atoms and allows the placement of stricter limits on the dust density in the lunar exosphere.