A discussion on supersymmetric cosmic strings with gauge-field mixing

Following a stream of investigation on supersymmetric gauge theories with cosmic-string solutions, we contemplate the possibility of building up a D and F term cosmic string by means of a gauge-field mixing in connection with a U(1)×U(1)′ symmetry. The spontaneous break of both gauge symmetry and supersymmetry are thoroughly analysed and the fermion zero modes are worked out. The role of the gauge-field mixing parameter is elucidated in connection with the string configuration that comes out. As an application of the model presented here, we propose the possibility that the supersymmetric cosmic-string yields the production of fermionic charge carriers that may eject, at their late stages, particles that subsequently decay to produce cosmic rays of ultra-high energy. In our work, it turns out that massive supersymmetric fermionic partners may be produced for a SUSY breaking scale in the range 1011–1013 GeV, which is compatible with the phenomenology of a gravitino mass at the TeV scale. We also determine the range of the gauge-field mixing parameter, α, in connection with the mass scales of the present model.