AsterX: a new open-source GPU-accelerated GRMHD code for dynamical spacetimes*

As the demand for extensive parallel computing grows to tackle various astrophysical challenges through numerical simulations, the necessity for codes capable of efficient GPU utilization becomes increasingly apparent. In this presentation, I will delve into the distinctive features of AsterX, a novel open-source code for general relativistic magnetohydrodynamics (GRMHD). AsterX is built upon CarpetX, a cutting-edge driver within the Einstein Toolkit. It employs the flux-conservative Valencia formulation, incorporating staggered vector potential evolution. Tailored for GPU performance, AsterX maximizes the advantages of block-structured adaptive mesh refinement, seamlessly integrated via CarpetX and the AMReX framework. While still in development, AsterX undergoes rigorous testing on high-performance clusters like Frontera and Frontier, demonstrating successful completion of some demanding GRMHD tests.