Chiral gravitational waves produced in a helical magnetogenesis model

We investigate the gravitational wave production induced by the primordial magnetic fields in a parity-violating magnetogenesis model. It is shown that the gravitational waves detectable by LISA, DECIGO or BBO and the magnetic fields strong enough to explain the blazar observation can be simultaneously produced. The magnetic fields and the gravitational waves have the same chirality and their amplitudes are related, which may also be tested by future observations. (paper)