Collimated outflows from long-lived binary neutron star merger remnants

Understand

The connection between short gamma-ray bursts (SGRBs) and binary neutron star (BNS) mergers was recently confirmed by the association of GRB 170817A with the merger event GW170817.

• However, no conclusive indications were obtained on whether the merger remnant that powered the SGRB jet was an accreting black hole (BH) or a long-lived massive neutron star (NS).
• Here, we explore the latter case via BNS merger simulations covering up to 250 ms after merger.
• We report, for the first time in a full merger simulation, the formation of a magnetically-driven collimated outflow along the spin axis of the NS remnant.