# A2b: Vector-Boson Scattering and Multi-Boson Production

Principal Investigators
Prof. Wolfgang Kilian University of Siegen
Prof. Dieter Zeppenfeld Karlsruhe Institute of Technology

### Subject

We study processes at the LHC which involve interactions of four or more electroweak vec- tor or Higgs bosons. If there is new physics in the Higgs or electroweak sector, we expect deviations from the SM in vector-boson scattering and multi-boson production. The deviati- ons rise with energy and thus become significantly constrained by unitarity relations. We develop universal schemes for dealing with this fact, properly matched to the effective- theory description at low energy.

### Topics

1. Vector-boson scattering:
• study all charged and neutral bosons (+ photon, + Higgs);
• compare and combine analytical and numerical methods;
• match to D=6 ⊕ D=8 low energy effective operators coherently; signal vs background separation for future LHC run;
2. Predictions and limits for $q \bar q \to n$~bosons ($n > 2$):
• disentangle and relate final states in $q \bar q \to VVV$ and $VVVV$;
• visible and invisible new physics as inelastic scattering;
3. Combine predictions and apply to incoming LHC results:
• unitarity relations apply to all multi-boson processes coherently;
• complete simulations and tools for meaningful data analysis;
• implications for effective theory and (simplified) models;
• model-independent interpretation and sensitivity to Higgs potential.