Helicity Selection Rules and Non-Interference for BSM Amplitudes

Abstract

Precision studies of scattering processes at colliders provide powerful indirect constraints on new physics. We study the helicity structure of scattering amplitudes in the SM and in the context of an effective Lagrangian description of BSM dynamics. Our analysis reveals a novel set of helicity selection rules according to which, in the majority of 2 to 2 scattering processes at high energy, the SM and the leading BSM effects do not interfere. In such situations, the naive expectation that dimension-6 operators represent the leading BSM contribution is compromised, as corrections from dimension-8 operators can become equally (if not more) important well within the validity of the effective field theory approach.

12 pages, 2 figures

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Cited by in corpus (4)

• Anomalous Triple Gauge Couplings in the Effective Field Theory Approach at the LHC
• An NLO QCD effective field theory analysis of $W_{}^{+}{W}_{}^{-}$ production at the LHC including fermionic operators
• Novel measurements of anomalous triple gauge couplings for the LHC
• Precision Probes of QCD at High Energies