  We present the gravitational waveforms computed in ab initio two-dimensional
core collapse supernova models evolved with the Chimera code for progenitor
masses between 12 and 25 solar masses. All models employ multi-frequency
neutrino transport in the ray-by-ray approximation, state-of-the-art weak
interaction physics, relativistic transport corrections such as the
gravitational redshift of neutrinos, two-dimensional hydrodynamics with the
commensurate relativistic corrections, Newtonian self-gravity with a general
relativistic monopole correction, and the Lattimer-Swesty equation of state
with 220 MeV compressibility, and begin with the most recent Woosley-Heger
nonrotating progenitors in this mass range. All of our models exhibit robust
explosions. Therefore, our waveforms capture all stages of supernova
development: 1) a relatively short and weak prompt signal, 2) a quiescent
stage, 3) a strong signal due to convection and SASI activity, 4) termination
of active accretion onto the proto-neutron star, and 5) a slowly increasing
tail that reaches a saturation value. Fourier decomposition shows that the
gravitational wave signals we predict should be observable by AdvLIGO for
Galactic events across the range of progenitors considered here. The
fundamental limitation of these models is in their imposition of axisymmetry.
Further progress will require counterpart three-dimensional models, which are
underway.
