On flavourful Easter eggs for New Physics hunger and lepton flavour universality violation.
Eur Phys J C Part Fields
; 77(10): 688, 2017.
Article
em En
| MEDLINE
| ID: mdl-31997924
ABSTRACT
Within the standard approach of effective field theory of weak interactions for Δ B = 1 transitions, we look for possibly unexpected subtle New Physics effects, here dubbed "flavourful Easter eggs". We perform a Bayesian global fit using the publicly available HEPfit package, taking into account state-of-the-art experimental information concerning these processes, including the suggestive measurements from LHCb of R K and R K ∗ , the latter available only very recently. We parametrise New Physics contributions to b â s transitions in terms of shifts of Wilson coefficients of the electromagnetic dipole and semileptonic operators, assuming CP-conserving effects, but allowing in general for violation of lepton flavour universality. We show how optimistic/conservative hadronic estimates can impact quantitatively the size of New Physics extracted from the fit. With a conservative approach to hadronic uncertainties we find nonzero New Physics contributions to Wilson coefficients at the level of â¼ 3 σ , depending on the model chosen. Furthermore, given the interplay between hadronic contributions and New Physics effects in the leptonic vector current, a scenario with nonstandard leptonic axial currents is comparable to the more widely advocated one with New Physics in the leptonic vector current.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Eur Phys J C Part Fields
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Itália