Cosmic strings coupled with gravitational and electromagnetic waves

Two families of (time-dependent) cylindrically symmetric solutions of the Einstein-Maxwell electrovacuum equations are obtained. They admit a regular axis, they are free from curvature singularities, and they are asymptotically flat away from the axis. For general values of the parameters the solutions exhibit an angle deficit in going around the axis and they are interpreted as describing stable, open, cosmic strings, coupled with gravity and electromagnetism in the manner of general relativity. For particular values of the parameters the angle deficit is eliminated and the solution describes the propagation of nonradiating gravitational and electromagnetic waves. The two families are algebraically special, of Petrov type D