Figure 1: (Top panel) Spherical halo of scattered atoms created by four-wave mixing processes. (Bottom panel) The CSI coefficient $C$ as a function of the number of zones $M=V_{\text{data}}/V$. The atomic sphere was cut into $8$ polar and $2$–$80$ azimuthal zones. The arrangement of zones for $M=16$ and $M=32$ is depicted in the upper bottom panel [3].