SPATIAL-DISTRIBUTION OF ATOMS IN A MAGNETOOPTICAL TRAP

We present a theoretical analysis to explain the origin of different s patial distributions of laser-cooled sodium atoms in a magneto-optical trap. Such distributions, which include spherical clouds, rings, and rings with cores, are attributed to the radiation pressure due to misa ligned Gaussian beams acting on each individual atom. The predictions of this theory are confirmed by experimental observations reported ear lier. We were able to construct a diagram with several domains corresp onding to the stable structures observed.