GWs from two simulations of the s12 progenitor. The right column shows the signals from the simulation with energy-dependent neutrino transport and the left column shows the corresponding simulation performed with our gray neutrino transport. The top row shows the strain as a function of time and the bottom row shows the square of the short time Fourier transform calculated with scipy.signal.stft (Virtanen et al. 2020). The color scale is logarithmic, and the plots were normalized by a common factor.