%0 Journal Article
%T Scalar contributions to b -> c(u) tau nu transitions
%A Celis, A.
%A Jung, M.
%A Li, X. Q.
%A Pich, A.
%J Physics Letters B
%D 2017
%V 771
%I Elsevier Science Bv
%@ 0370-2693
%G English
%F Celis_etal2017
%O WOS:000406183300024
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=3260), last updated on Mon, 11 Sep 2017 12:48:30 +0000
%X We perform a comprehensive analysis of scalar contributions in b -> c tau nu transitions including the latest measurements of R(D-(*)), the q(2) differential distributions in B -> D-(*) tau nu the tau polarization asymmetry for B -> D*tau nu, and the bound derived from the total width of the B-c meson. We find that scalar contributions with the simultaneous presence of both left- and right-handed couplings to quarks can explain the available data, specifically R(D-(*)) together with the measured differential distributions. However, the constraints from the total B-c width present a slight tension with the current data on B -> D*tau nu in this scenario, preferring smaller values for R(D*). We discuss possibilities to disentangle scalar new physics from other new-physics scenarios like the presence of only a left-handed vector current, via additional observables in B -> D(*)tau nu decays or additional decay modes like the baryonic Lambda(b) -> Lambda(c)tau nu and the inclusive B -> X-c tau nu decays. We also analyze scalar contributions in b -> u tau nu transitions, including the latest measurements of B -> tau nu providing predictions for Lambda(b) -> p tau nu and B -> pi tau nu decays. The potential complementarity between the b -> u and b -> c sectors is finally investigated once assumptions about the flavour structure of the underlying theory are made.
%R 10.1016/j.physletb.2017.05.037
%U http://arxiv.org/abs/1612.07757
%U https://doi.org/10.1016/j.physletb.2017.05.037
%P 168-179