Improving new physics searches with precision: Sudakov logarithms up to the two-loop level

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A major aim of the ongoing experiments at the Large Hadron Collider (LHC) is the hunt for phenomena beyond the Standard Model (SM). These phenomena are extremely hard to come by - very small event rates for new physics processes are typically swamped by enormous backgrounds due to SM interactions. In fact, without a clear sign of new physics in terms of new resonances, we are required to look for very small percent-level deviations in the tails of distributions measured in very complex final states. Experimentally, percent-level precision will be achievable in the near future. However, matching this remarkable precision in theory predictions is a true challenge that requires to incorporate higher-order corrections in perturbation theory. At hadron colliders like the LHC we are primarily concerned with higher-order QCD corrections in order to improve our theoretical modelling. However, far above the electroweak (EW) scale higher-order EW corrections are strongly enhanced due to the appearance of Sudakov logarithms, which are universal and generated by well-defined structures of the contributing loop amplitudes at a given perturbative order. These corrections can easily reach a similar level as QCD higher-order corrections at hadron colliders. Thanks to recent advances in the automation of next-to-leading order EW corrections any SM process up to high particle multiplicity can now be evaluated including EW corrections. In order to further improve the predictions and in particular to arrive at reliable uncertainty estimates of the EW corrections the project at hand should develop an automated implementation of the Denner-Pozzorini algorithm for the calculation of EW Sudakov logarithms up to the two-loop level. As a first step the implementation of one-loop EW Sudakov logarithms should be foreseen, which is already available in the literature and can thus easily be validated. The implementation relies on the factorization of EW Sudakov logarithms with respect to the Born process valid up to the next-to-next-to logarithmic order. Once the described implementation is available phenomenological studies will be performed exploiting the newly archive precision and control of theoretical uncertainties. In particular this will concern the production of vector bosons in the vector-boson-fusion and vector-boson-scattering topologies, which both allow for stringent indirect searches for new physics.