Lunar Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2

Dust, Extinction, Planetary Systems

Scientific paper

Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEEs). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 μm size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEEs discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Lunar Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments 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 Lunar Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lunar Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1863066

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.