Abstract
We perform binary neutron star (BNS) merger simulations in full dynamical general relativity with illinoisgrmhd, on a Cartesian grid with adaptive-mesh refinement. After the remnant black hole has become nearly stationary, the evolution of the surrounding accretion disk on Cartesian grids over long timescales (∼1 s) is suboptimal, as Cartesian coordinates over-resolve the angular coordinates at large distances, and the accreting plasma flows obliquely across coordinate lines dissipating angular momentum artificially from the disk. To address this, we present the handoff, a set of computational tools that enables the transfer of general relativistic magnetohydrodynamic (GRMHD) and spacetime data from illinoisgrmhd to harm3d, a GRMHD code that specializes in modeling black hole accretion disks in static spacetimes over long timescales, making use of general coordinate systems with spherical topology. We demonstrate that the handoff allows for a smooth and reliable transition of GRMHD fields and spacetime data, enabling us to efficiently and reliably evolve BNS dynamics well beyond merger. We also discuss future plans, which involve incorporating advanced equations of state and neutrino physics into BNS simulations using the handoff approach.
| Original language | English |
|---|---|
| Article number | 083015 |
| Journal | Physical Review D |
| Volume | 106 |
| Issue number | 8 |
| DOIs | |
| State | Published - Oct 15 2022 |
Funding
This work was primarily funded through NASA Award No. TCAN-80NSSC18K1488, which provides support to all authors. Additionally, F. L. A., M. C., L. E. L. J., and Y. Z. thank the NSF for support on Grants No. PHY-2110338, No. AST-2009330, No. OAC-2031744 and No. OAC-2004044. Z. B. E. and L. R. W. gratefully acknowledge support from NSF Awards No. PHY-1806596, No. PHY-2110352, and No. OAC-2004311, as well as NASA Award No. ISFM-80NSSC18K0538. R. O’S. is supported by NSF Awards No. PHY-2012057, No. PHY-1912632, and No. AST-1909534. B. J. K. is supported by NASA under Award No. 80GSFC21M0002. A. M-B is supported by the UCMEXUS-CONACYT Doctoral Fellowship, and NASA through the NASA Hubble Fellowship Grant No. HST-HF2-51487.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under Contract No. NAS5-26555. V. M. is supported by the Exascale Computing Project (17-SC-20-SC), a collaborative effort of the U.S. Department of Energy (DOE) Office of Science and the National Nuclear Security Administration. Work at Oak Ridge National Laboratory is supported under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. Computational resources were provided by the TACC’s Frontera supercomputer Allocations No. PHY-20010 and No. AST-20021. Additional resources were provided by the RIT’s BlueSky and GreenPrairies and Lagoon Clusters acquired with NSF Grants No. PHY-2018420, No. PHY-0722703, No. PHY-1229173, and No. PHY-1726215. F. L. A. would like to thank Luciano Combi for helpful comments and discussion.