Studies In Theoretical Astrophysics and General Relativity
Our research focuses on simulations of plausible relativistic astrophysical scenarios involving compact objects. The main thrust is to use our powerful and robust Illinois GRMHD code, which has been built over many years on the Cactus infrastructure and uses the Carpet code for adaptive mesh refinement, but employs our own algorithms and coding. We have used it successfully to tackle a plethora of astrophysical scenarios involving compact objects such as the merger of magnetized binary neutron stars and binary black hole–neutron stars as well as the merger of binary black holes, both in vacuum and in circumbinary magnetized disks. This code utilizes state-of-the-art, high resolution, shock capturing methods to evolve scenarios involving either vacuum or matter spacetimes, with or without B-fields. It utilizes the BSSN formulation of the Einstein field equations with puncture gauge conditions. It solves the magnetic induction equation by introducing a vector potential and employs a generalized Lorentz gauge condition to reduce the spurious appearance of strong B-fields on refinement level boundaries. With the goal of facilitating community involvement in the code's use and development, as well as the minimization of human effort in generating new science, we are in the process of porting our Illinois GRMHD code and its diagnostics and tests to the Einstein Toolkit infrastructure.