The role of families in determining collision probability in the asteroid main belt

Asteroid families represent the outcomes of major collisional events in the asteroid Main Belt. These events produced in some cases huge numbers of fr agments, down to sizes of at least I km in diameter. In this paper we show that these families produce a significant increase in the "local" collision rate by as much as an order of magnitude relative to the average collision rate of the entire Belt. This fact should be taken into account in future studies of the collisional evolution of the Main Belt. (C) 2001 Academic Pr ess.