  We conduct an exhaustive search for solutions of IIA and IIB supergravity
with augmented supersymmetry. We find a two-parameter family of IIB solutions
preserving 28 supercharges, as well as several other IIA and IIB families of
solutions with 24 supercharges. Given the simplicity of the pp-wave solution,
the algorithm described here represents a systematic way of classifying all
such solutions with augmented supersymmetry. By T-dualizing some of these
solutions we obtain exact non-pp wave supergravity solutions (with 8 or 16
supercharges), which can be interpreted as perturbations of the AdS-CFT
correspondence with irrelevant operators.

High Energy Physics - Theory