Method for velocimetry of cold atoms

We describe our use of recoil-induced resonances or stimulated optical Compton scattering to measure the velocity distribution of laser-cooled cesium atoms in one dimension. The technique works well at velocities near 1 cm/s, is insensitive to the effects of light shifts or stray fields, requires only a few ${\mathrm{mm}}^3$ of work space, and may be completed in 1 ms. It may be extended to allow the measurement of velocity distributions in three dimensions and for in situ measurements in optical molasses, traps, or lattices. Our measurements are compared with traditional ballistic measurements in the same apparatus.