Seminarium Teorii Oddziaływań Elementarnych

While several approaches and their implementations for the efficient calculation of scattering amplitudes within collinear factorization applied to hadron scattering exist, no automated tools exist to achieve the same within frameworks of factorization that allow for the initial-state partons, entering the hard partonic process, to have non-vanishing transversal momentum components. I will present a prescription to construct manifestly gaugeinvariant tree-level amplitudes with one or two off-shell initial-state gluons for processes with arbitrary particles in the final state, and will show that the prescription allows for calculations that are efficient and easy to automate.