  Certain numerical frameworks used for the evolution of binary black holes
make use of a gamma driver, which includes a damping factor. Such simulations
typically use a constant value for damping. However, it has been found that
very specific values of the damping factor are needed for the calculation of
unequal mass binaries. We examine carefully the role this damping plays, and
provide two explicit, non-constant forms for the damping to be used with
mass-ratios further from one. Our analysis of the resultant waveforms compares
well against the constant damping case.

General Relativity and Quantum Cosmology