Vol. 622
In section 2. Astrophysical processes

Kinetic modeling of the electromagnetic precursor from an axisymmetric binary pulsar coalescence

by B. Crinquand, B. Cerutti, and G. Dubus, 2019, A&A, 622, A161 alt

Neutron stars merging in a gravitational-wave emitting death spiral is no longer speculation: now begins the task of understanding the collective multiwavelength phenomenology. This paper presents a simulation - schematic but not unrealistic - of the merger of two field-aligned neutron stars along their lines of center. Although orbital motion is not included and the fields are axisymmetric, the magnetospheres and toroidal field and accelerating potentials are self-consistently treated within a relativistic PIC code. The antiparallel case shows a plateau-like precursor in the high energy emission, and in situ particle acceleration is studied in the resulting current sheet connecting the magnetospheres. Although these simulations are still too idealized for direct comparison with current observation, they are a harbinger of things to come.