  Considering light-mediated long-range interactions between cold atoms in a
magneto-optical trap (MOT), we present numerical evidence of a nonequilibrium
steady state (NESS) for sufficiently large number of atoms (> 10^8). This state
manifests itself as the appearance of an anisotropic distribution of velocity
when a MOT approaches the threshold beyond which self-oscillating instabilities
occur. Our three-dimensional (3D) spatiotemporal model with nonlocal spatial
dependencies stemming from the interatomic interactions has recently been
compared successfully to predict different instability thresholds and regimes
in experiments with rubidium atoms. The behavior of the NESS is studied as a
function of the main MOT parameters, including its spatiotemporal
characteristics.
