  Self-organized patterns of spots on a at metallic anode in a cylindrical glow
dis- charge tube are simulated self-consistently. A standard model of a glow
discharge is used, comprising conservation and transport equations for a single
species of ion and electrons, written with the use of the drift-diffusion and
local-field approximations, and the Poisson equation. The computation domain is
the region from the anode to the discharge column; only processes in the
near-anode region are considered. Multiple solutions, existing in the same
range of discharge current and describing modes with and without anode spots,
are computed by means of a stationary solver. The computed spots exhibited
unexpected behavior. A reversal of the local anode current density in the
middle of each of the spots was found, i.e. mini-cathodes are formed inside the
spots. The solutions do not fit into the conventional pattern of
self-organization in bistable nonlinear dissipative systems; e.g. the modes are
not joined by bifurcations.
