X-ray fluorescence modelling for Solar system regoliths: Effects of viewing geometry, particle size, and surface roughness

摘要

Soft X-ray fluorescent emission from the surfaces of asteroids and other atmosphere-less solar-system objects is studied using ray-tracing techniques. X-ray observations allow theassessment of the elemental composition and structure of the surface. The model regolith isassumed to consist of close-packed uniformly distributed spherical particles of equal size. Thesurface is also assumed to be rough according to a fractional-Brownian-motion model. The flu-orescent X-ray emission from regolith surfaces is simulated in order to better understand thecontribution of viewing-geometry -related phenomena on the signal obtained from, e.g., orbitingplatforms. The first results are presented and the applicability of the methods to the interpre-tation of future asteroid and Mercury mission X-ray data (e.g., BepiColombo) is discussed.