Comparison of $t\bar{t}W$ theory predictions in the $3\ell$ channel

We report on our recent comparison of various theoretical approaches to predict fiducial signatures for $pp\to t\bar{t}W$ in the $3\ell$ decay channel at $\mathcal{O}(\alpha_s^3\alpha^6)$ and $\mathcal{O}(\alpha_s\alpha^8)$. The comparison includes fixed-order predictions including full off-shell effects as well as predictions based only on the double-resonant contributions by employing the Narrow-Width-Approximation. Furthermore, we include parton-shower matched predictions using the MG5 and POWHEG-BOX frameworks.