Penrose Limits of Non-standard Brane Intersections

TL;DR

This paper investigates the Penrose limits of a specific non-standard brane intersection geometry, analyzing supersymmetry properties and deriving the corresponding pp-wave solutions with enhanced supersymmetry at a special rotation angle.

Contribution

It provides a detailed study of the Penrose limit of a non-standard brane intersection, revealing conditions for supernumerary supersymmetry and deriving the associated string actions.

Findings

Supernumerary Killing spinors occur at a 45-degree rotation angle.

The light-cone string action exhibits linearly-realised supersymmetry at this angle.

Multiple constant field strengths support the resulting pp-wave solutions.

Abstract

The non-standard intersection of two 5-branes and a string can give rise to AdS_3\times S^3\times S^3\times S^1. We consider the Penrose limit of this geometry and study the supersymmetry of the resulting pp-wave solution. There is a one-parameter family of Penrose limits associated with the orthogonal rotation of the two foliating circles within the two 3-spheres. Supernumerary Killing spinors arise only when the rotation angle is 45 degrees, for which case we obtain the corresponding light-cone string action that has linearly-realised supersymmetry. We also obtain Penrose limits of other non-standard intersections that give rise to the product of AdS_3 or AdS_2 and two spheres. The resulting pp-waves are supported by multiple constant field strengths.