  When two of three pairs of the Gaussian laser beams of a traditional MOT are
misaligned in the racetrack configuration the effective coordinate-dependent
vortex force do arise. Then an atom is accelerated by this vortex force until
its velocity not balanced by the damping force. This situation may produce a
stable ring of revolving atoms of a certain radius. Due to the different
frequency and laser beams intensity dependences of the vortex, damping and
trapping forces it is possible to equalize the radii of two orbiting groups of
atoms in two-species or dual-isotope magneto-optical trap and so to arrange a
continuing collider of cooled atoms with the prescribed relative velocity. A
collider setup for atoms of two different types rotating with different angular
velocities along the same ring-like trajectory into MOT of the conventional
six-beam geometry is proposed and designed on example of two rubidium isotopes
Rb85 and Rb87.
