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.
Helicity Selection Rules and Non-Interference for BSM Amplitudes / Azatov, Aleksandr; Contino, Roberto; Machado, Camila S.; Riva, Francesco. - In: PHYSICAL REVIEW D. - ISSN 2470-0010. - 95:6(2017), pp. 1-11. [10.1103/PhysRevD.95.065014]
Helicity Selection Rules and Non-Interference for BSM Amplitudes
Azatov, Aleksandr;
2017-01-01
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.File | Dimensione | Formato | |
---|---|---|---|
PhysRevD.95.065014.pdf
accesso aperto
Tipologia:
Versione Editoriale (PDF)
Licenza:
Creative commons
Dimensione
327.83 kB
Formato
Adobe PDF
|
327.83 kB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.