Quasi-equilibrium binary black hole initial data

This web-site makes publicly available some of the initial data sets computed with the quasi-equilibirum method and with isolated horizon boundary conditions (Cook & Pfeiffer, PRD 70, pp. 104016 (2004)). For each data set, the spatial 3-metric, extrinsic curvature, lapse and shift in Cartesian coordinates are available, and C++ routines are supplied for interpolation of the data to any desired (Cartesian) coordinate location.

Greg (Cook) and Harald (Pfeiffer) hope these data sets will provide a common starting point for the numerical relativity community, to faciliate comparisons between different codes, and for validation of the obtained results.

In publications and talks, please acknowledge that the initial data were supplied by me and cite

• Cook & Pfeiffer, PRD 70, 104016 (2004)
• Pfeiffer, Kidder, Scheel & Teukolsky, Comp. Phys. Comm., 152, pp. 253-273 (2003)

Library to interpolate data sets & test-data

There are two options: Either with a standalone executable, or via a library which must be linked into your executable.

Standalone executable
Reads coordinates from stdin, and outputs the interpolated data to stdout.

Library
The following files must be linked into your own executable:

• PublicID.hpp: Header file declaring the functions to be used for interpolation (documentation inside).
• libSpEC_ID.a: Library containing the necessary interpolation routines defined in PublicID.hpp. This version is compiled with gcc 3.4.3 (which comes with Fedora Core 3 and RHE 4), and may not work with older versions of gcc. It has also debugging enabled; I will make an optimized version available, when I am reasonably sure that this setup works. Please contact me if you need this library for other compilers.
• InterpolationExample.cpp: A simple executable demonstrating how to use PublicID.hpp (documentation inside).
• Kerr-Schild inital data for a unit-mass Schwarzschild black hole at the origin. This data-set is used in InterpolationExample.cpp

Update I've just updated to g++ version 3.4.4, and have recompiled the libraries. If interpolation works fine with the libraries above, there is no reason not to try these: InterpolateSpECID_gcc344 libSpEC_ID_gcc344.a

Update (Apr 6, 2006) Executable compiled with Pathscale compilers on an Opteron system:
InterpolateSpECID_pathCC_Opteron

Update (May 22, 2006): Executable and library compiled with Intel V9.0 on NCSA's Cobalt system (SGI Altix/Itanium 2).
InterpolateSpECID_Cobalt_icc9_debug
libSpEC_ID_Cobalt_icc9_debug.a
(Debugging is enabled, so these executables are large and slow)

Binary black hole initial data (corotating)

These data-sets use Eq. (59a) or (59b) as boundary condition on the lapse. Eq. (59b) corresponds precisely to Table IV of Cook & Pfeiffer, 2004. P/E_ADM represents approximately the orbital period of the binary in units of the ADM-mass. Finally, some explanations common to all data sets.

If you have no preference between the two families of initial data, I suggest to use Boundary condition Eq. (59a). The hope beyond this suggestion is to have as many groups as possible evolving precisely the same initial data to facilitate comparisons.

NOTE: Our current web-server has very limited disk-space. Therefore, some of the links below may temporarily not work. In this case, please email me and I will restore the data sets. This restriction will disappear soon when we move to a new web-server.

Binary black hole initial data (non-spinning)

These data-sets use Eqs. (59a) or (59b) of Cook & Pfeiffer 2004 as boundary condition on the lapse. Eq. (59b) corresponds precisely to Table V of Caudill, Cook, Grigsby & Pfeiffer, 2006. P/E_ADM represents approximately the orbital period of the binary in units of the ADM-mass. Finally, some explanations common to all data sets.

libSpEC_ID-g++4.1.2-0ubuntu4.a (compiled with g++ version 4.1.2 on an Ubuntu Intel Pentium M machine)