Numerical modeling of main belt collisional evolution: depletion effects

Within the framework of a new general numerical model aimed at simulating the collisional evolution of the asteroid Main Belt, we are considering how the presence of depletion effects may affect the evolution of the size distribution. Depletion effects are related to gravitational perturbations (secular and mean motion resonances, chaos and so on) as well as to non-gravitational terms including Poynting-Robertson effects on dust and the Yarkovsky mechanism (affecting larger bodies with sizes from a few tens of cm to -say-20 km). We are including these terms in the present version of the model, taking into account that they (especially the Yarkovsky effect) may be considered as a steady process of mass depletion from the Belt, affecting particular size ranges. Consequently, they might contribute to the formation of "waves" in the resulting size distribution of the population. Preliminary results are presented.