Abstract
A spherical particle which is illuminated by a light beam in an infinite expanse of a uniform gas is considered. The flow induced around the particle and the force acting on it are investigated for small Knudsen number (the mean free path of the gas molecules divided by the radius of the particle) on the basis of the asymptotic theory for Boltzmann equation. The velocity of steady motion of the particle in the absence of any constraint is also obtained.
