Cerenkov radiation of superconducting cosmic strings
Gal'tsov D. V., GratsYu. V., Lavrent'ev A. B.
A collision of rectilinear superconducting cosmic strings is accompanied by the emission of electromagnetic radiation if the velocity of the intersection point exceeds the velocity of light. This effect stems from a gravitational interaction of the strings. It can be thought of as a realization of Ginzburg's mechanism of radiation from a superluminous reflection of a light beam.