Properties of nodal domains in a pseudointegrable barrier billiard.

We investigate experimentally the scaling properties of the number of nodal domains of the wave functions and the distribution of the nodal domain areas in a pseudointegrable barrier billiard. The number of nodal domains is smaller than expected for billiards whose dynamics is chaotic or regular. This reduction is explained by the appearance of superscars in the barrier billiard, i.e., regular structures, which are embedded into the underlying chaotic wave functions. Furthermore, the area distribution of nodal domains follows the predictions of a percolation model for chaotic systems.