The Next Generation of Binary Black Hole Head-On Collisions, and their Aftermath

Open Access
Kelly, Bernard Joseph
Graduate Program:
Doctor of Philosophy
Document Type:
Date of Defense:
April 08, 2004
Committee Members:
  • Lee S Finn, Committee Member
  • Bernd Bruegmann, Committee Member
  • Pablo Laguna, Committee Chair
  • Steinn Sigurdsson, Committee Member
  • binary black hole
  • merger
  • stability
  • wave forms
I present new results in the full 3D evolution of black hole binary systems, for the head-on collision case. In contrast to most prior work on this problem, the initial data used is not restricted to conformally flat data sets, and the curvature singularities are not locked to the same static coordinate location on the computational domain. With my collaborators, I have succeeded in producing long-term stable evolutions using a combination of modern techniques: an adjusted BSSN evolution system with densitized lapse function; dynamic excision of singularities, with automatic re-centering; analytic pre-merger slicing conditions pre-merger; and live ``driver' slicing conditions post-merger. The resulting evolutions are the first stable mergers of Kerr-Schild-like black holes using singularity excision. I present the results of this work for two regimes: holes with small initial separation, which represent highly distorted single black holes, and holes with large initial separation, which must undergo in-fall and merger. This work is intended to complement earlier axisymmetric simulations, and recent evolutions of binaries using very different techniques. To accompany these full 3D evolutions, I also present published work on the use of derived wave forms to test the self-consistency of general relativity. The test described will be applicable to current and future interferometric gravitational-wave observatories, including LIGO and LISA.