An accreting black hole binary system (ABHB) consists of a star orbiting a small black hole. One particularly interesting example is a neutron star-black hole (NS-BH) binary, which may be interesting sources of gravitational waves for gravitational wave observatories such as Advanced LIGO. The gravitational and electromagnetic wave signals from NS-BH binaries contains information about the particular evolution of the binary, including magnetic effects and the disruption of the neutron star by the tidal forces of the black hole.
This award supports the development of computational infrastructure and techniques to study ABHBs and related systems. This includes the further development of HAD, a freely available, modular computational toolkit for solving differential equations in a distributed parallel environment. HAD provides sophisticated adaptive mesh refinement capabilities, which allow the user to combine different types of differential equations and/or numerical methods. Techniques for solving the Einstein equations and magnetohydrodynamics (MHD) equations will be further developed and implemented in the code to meet the demands of simulating ABHB systems and extracting valuable physical information.
This work serves to advance numerical techniques for an important scientific problem, as well as the creation and dissemination of advanced tools for distributed computing. The modular design of the infrastructure allows other researchers to share and extend these tools. Finally, this study involves the training of postdoctoral researchers, graduate students, and undergraduates.
