Charged macroscopic type-II strings and their networks

We write down charged macroscopic string solutions in type II string theories, compactified on tori, and present an explicit solution of the spinor Killing equations to show that they preserve 1/2 of the type II supersymmetries. The S-duality symmetry of the type IIB string theory in ten-dimensions is used to write down the SL(2, Z) multiplets of such strings and the corresponding 1/2 supersymmetry conditions. Finally we present examples of planar string networks, using charged macroscopic (p, q)-strings. An interesting feature of some of these networks, which preserve 1/4 supersymmetry, is a required alignment among three parameters, namely the orientation of strings, a U(1) phase associated with the maximal compact subgroup of SL(2, Z), and an (angular) parameter associated with a solution generating transformation, which is responsible for creating charges and currents on the strings.