  Dust grains with sizes around (sub)mm are expected to couple only weakly to
the gas motion in regions beyond 10 au of circumstellar disks. In this work, we
investigate the influence of the spatial distribution of such grains on the
(sub)mm appearance of magnetized protoplanetary disks. We perform non-ideal
global 3D magneto-hydrodynamic stratified disk simulations including particles
of different sizes (50 micron to 1 cm), using a Lagrangian particle solver. We
calculate the spatial dust temperature distribution, including the dynamically
coupled submicron-sized dust grains, and derive ideal continuum re-emission
maps of the disk through radiative transfer simulations. Finally, we
investigate the feasibility to observe specific structures in the thermal
re-emission maps with the Atacama Large Millimeter/submillimeter Array (ALMA).
The pressure bump close to the outer edge of the dead-zone leads to particle
trapping in ring structures. More specifically, vortices in the disk
concentrate the dust and create an inhomogeneous distribution of the solid
material in the azimuthal direction. The large-scale disk perturbations are
preserved in the (sub)mm re-emission maps. The observable structures are very
similar to those expected to result from planet-disk interaction. The larger
dust particles increase the brightness contrast between gap and ring
structures. We find that rings, gaps and the dust accumulation in the vortex
could be traced with ALMA down to a scale of a few astronomical units in
circumstellar disks located in nearby star-forming regions. Finally, we present
a brief comparison of these structures with those recently found with ALMA in
the young circumstellar disks of HL Tau and Oph IRS 48.
