Gamma-ray bursts from superconducting cosmic strings at large redshifts

Recent developments in the theory of superconducting cosmic strings suggest that their cusps may be possible sources of very intense and highly collimated bursts of energy. A cusp at a redshift z ≈ 1000 may give rise to an intense burst of energy with a duration of a few seconds or less. The maximum amount of energy associated with such an event is limited to 10⁷ergs cm⁻² by causality. If only one part in 10¹¹ of this energy reaches Earth as 1 MeV gamma rays, then about 100 gamma-ray bursts should be detectable every year with the existing instruments. Furthermore, microlensing of this tight beam is quite likely to produce images with dissimilar spectral and time profiles.