of field low-mass dwarfs derived from Sloan Digital Sky Survey Data Release 6 photometry.
The analysis incorporates ∼15 million low-mass stars (0.1 ${\cal M}_\odot <$ … For low-mass
stars, with lifetimes much greater than the Hubble time, the observed present-day mass
function (PDMF) in the field should trace the initial mass function (IMF). Following Salpeter (1955),
the IMF has usually been characterized by a power law $\psi ({\cal M}) = dN / d{\cal M} \propto …