Session D8 - Classical Gravitation.
ORAL session, Saturday afternoon, May 01
Governor's Square 17, Adam's Mark Hotel
At large mass, the initial mass function [IMF], which describes the size distribution of stellar objects, is characterized by a power-law with the Salpeter exponent. At small [substellar] mass, theory indicates that there must be some change in this power law. Indeed, direct observation indicates that the IMF is certainly modified below approximately one-tenth of a solar mass. We demonstrate that at very low mass the IMF should again be given by a power law with an exponent opposite in sign to the high-mass exponent. Furthermore, we verify that this low-mass exponent is in principle calculable via dynamical systems theory applied to gravitational collapse. Observational data indicate a broad agreement with the sign of the low-mass exponent, and a preponderance of evidence pointing to a critical mass-scaling exponent approximately equal to two.