Netherlands Research School for Astronomy (NOVA) | 2020 Oct 21
An international team of astrophysicists under Dutch leadership has demonstrated with an improved model that colliding neutron stars can emit gamma rays. Old models did not predict this and faltered since the merging of two neutron stars in 2017 that released gamma rays. ...© Philipp Mösta et al. (2020 ApJL)
The researchers, led by Philipp Mösta (University of Amsterdam), provided their model of colliding neutron stars with more variables than ever before. They considered, among other things, the theory of relativity, gas laws, magnetic fields, nuclear physics and the effects of neutrinos. The researchers ran their simulations on the Blue Waters supercomputer at the University of Illinois in Urbana-Champaign (United States) and on the Frontera supercomputer at the University of Texas, Austin (United States).
In the simulation, a ring is created around the merged neutron stars from which a thin strand of gamma radiation shoots up and down. This radiation then finds its way out like a whirlwind along the magnetic field lines of the merged stars. Furthermore, an hourglass-like cone moves up and down from the ring. This is where heavier elements such as gold possibly form. Gold is, like gamma rays, observed in the merging neutron stars in 2017 where a kilonova was formed. ...
A Magnetar Engine for Short GRBs and Kilonovae ~ Philipp Mösta et al