Scattering of Electroweak Gauge Bosons - Theoretical Concepts and Precise Predictions for the LHC

• Applicant: Professor Dr. Stefan Dittmaier
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2013 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 247816121

The experimental investigation of electroweak vector-boson scattering (VBS) processes is a cornerstone in the exploration of the mechanism of electroweak symmetry breaking at the LHC, thereby asking for predictions at the highest possible level. While results on QCD corrections to these processes exist in the literature, the core of the proposed project consists in the calculation of the remaining next-to-leading order (NLO) corrections that are of electroweak or mixed QCD/electroweak origin. The focus of the project is directed to like-sign and opposite-sign WW+2jet production, leaving the extension to other channels involving Z bosons to future projects. Apart from the full NLO calculations, which will be based on the approved methods for loop corrections worked out by A.Denner and the applicant, the project aims at the construction of appropriate approximations vector-boson scattering in the respective kinematic regime. It is expected that a phenomenologically sufficient approximation can be based on full LO calculations supplemented by NLO corrections treated via a systematically improved "effective vector-boson approximation". Such approximations would not only deliver a better theoretical understanding of VBS, but also facilitate the inclusion of higher-order corrections in multi-purpose Monte Carlo generators. Finally, the project represents an important pre-stage towards precise predictions for VBS in the presence of physics beyond the Standard Model, either in terms of concrete SM extensions or a model-independent effective theory with higher-dimensional operators.

• DFG Programme: Research Grants