Gamma-ray bursts and kilonova emission from magnetized accretion-induced collapse of white dwarfs

The nature of the central engine driving long-duration gamma-ray bursts accompanied by kilonova emissions, such as GRB 211211A and GRB 230307A, remains uncertain.

We demonstrate that the accretion-induced collapse of a strongly magnetized, rapidly rotating white dwarf can power gamma-ray bursts and kilonova emissions resembling those from neutron star mergers.

In particular, we present second-long axisymmetric, general relativistic neutrino magnetohydrodynamics simulations of such collapse, exploring four different initial magnetic field strengths.

We estimate the jet energy, analyze the properties of the matter outflow, and compute the associated light curves.

Our findings highlight the crucial role of magnetic fields in shaping the ejecta mass, its composition, and the formation of jets.

With sufficiently strong magnetic fields, the accretion-induced collapse of rapidly rotating white dwarfs may produce relativistic jets and be sites of heavy element nucleosynthesis.