  We investigated with MIDI the extension of dusty mid-infrared excess sources
(IRS 1W, IRS 10W, IRS 2, IRS 8) in immediate vicinity to the black hole (BH) at
the GC. We derive 3$\sigma$ upper limits of the correlated fluxes of our target
sources which give direct constraints on the size of the emitting regions. Most
probably the emission originates from bow shocks generated by windy stars
ploughing through the dense matter of the Northern MiniSpiral.
