  Within an effective Dirac-Weyl theory we solve the scattering problem for
massless chiral fermions impinging on a cylindrical time-dependent potential
barrier. The set-up we consider can be used to model the electron propagation
in a monolayer of graphene with harmonically driven quantum dots. For static
small-sized quantum dots scattering resonances enable particle confinement and
interference effects may switch forward scattering on and off. An oscillating
dot may cause inelastic scattering by excitation of states with energies
shifted by integer multiples of the oscillation frequency, which significantly
modifies the scattering characteristics of static dots. Exemplarily the
scattering efficiency of a potential barrier with zero bias remains finite in
the limit of low particle energies and small potential amplitudes. For an
oscillating quantum dot with finite bias, the partial wave resonances at higher
energies are smeared out for small frequencies or large oscillation amplitudes,
thereby dissolving the quasi-bound states at the quantum dot.
