Lifetime of B_{c}
Phys Rev Lett
; 118(8): 081802, 2017 Feb 24.
Article
em En
| MEDLINE
| ID: mdl-28282199
ABSTRACT
We investigate a new constraint on new-physics interpretations of the anomalies observed in BâD^{(*)}τν decays making use of the lifetime of the B_{c}^{-} meson. A constraint is obtained by demanding that the rate for B_{c}^{-}âτ^{-}ν[over ¯] does not exceed the fraction of the total width that is allowed by the calculation of the lifetime in the standard model. This leads to a very strong bound on new-physics scenarios involving scalar operators since they lift the slight, but not negligible, chiral suppression of the B_{c}^{-}âτ^{-}ν[over ¯] amplitude in the standard model. The new constraint renders a scalar interpretation of the enhancement measured in R_{D^{*}} implausible, including explanations implementing extra Higgs doublets or certain classes of leptoquarks. We also discuss the complementarity of R_{D^{(*)}} and a measurement of the longitudinal polarization of the τ in the BâD^{*}τν decay in light of our findings.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Phys Rev Lett
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Suíça
País de publicação:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA