\label{fig:distributions}
The eight $f_i(x,\cos\theta)$ functions and the standard model contribution $S^0(x,\cos\theta)$. Left column, from top to bottom: $f_1 = f_A^\gamma$~; $f_3 = f_B^\gamma$~; $f_5 = f_C^\gamma$~; and $f_7 = f_D^\gamma$. Right column, from top to bottom: $f_2 = f_A^Z$~; $f_4 = f_B^Z$~; $f_6 = f_C^Z$~; $f_8 = f_D^Z$~; and $S^0$. In all these figures, $\theta$ is the lepton polar angle, and $x$ is the reduced lepton energy, defined as $x = {2 E_\ell \over m_t} \sqrt{1-\beta \over 1+ \beta}$, where $\beta$ is the top velocity and $m_t$ is the top mass.