@Article{Penalva_etal2024, author="Penalva, N. and Flynn, J. M. and Hernandez, E. and Nieves, J.", title="Study of new physics effects in (B)over-bars {\textrightarrow} Ds(*) $\tau$-($\nu$)over-bar $\tau$ semileptonic decays using lattice QCD form factors and heavy quark effective theory", journal="Journal of High Energy Physics", year="2024", publisher="Springer", volume="01", number="1", pages="163--33pp", optkeywords="Effective Field Theories of QCD; Flavour Symmetries; Semi-Leptonic Decays; SMEFT", abstract="We benefit from the lattice QCD determination by the HPQCD of the Standard Model (SM) form factors for the (B) over bar (s) -> D-s [Phys. Rev. D101(2020) 074513] and the SM and tensor ones for the (B) over bar (s) -> D-s* (arXiv:2304.03137[hep-lat]) semileptonic decays, and the heavy quark effective theory (HQET) relations for the analogous B -> D-(*()) decays obtained by F.U. Bernlochner et al. in Phys. Rev. D95(2017) 115008, to extract the leading and sub-leading Isgur-Wise functions for the (B) over bar (s) -> D-s(()*()) decays. Further use of the HQET relations allows us to evaluate the corresponding scalar, pseudoscalar and tensor form factors needed for a phenomenological study of new physics (NP) effects on the (B) over bar (s) -> D-s(()*()) semileptonic decay. At present, the experimental values for the ratios R-D(*) = Gamma[ (B) over bar -> D-(*())(tau- (nu) over bar tau)]/Gamma[(B) over bar -> D-(*())e(-)(mu(-)) (nu) over bar (e(mu))]are the best signal in favor of lepton flavor universality violation (LFUV) seen in charged current (CC) b -> c decays. In this work we conduct a study of NP effects on the (B) over bar (s) -> D-s(()*()) tau(-)(tau) semileptonic decays by comparing tau spin, angular and spin-angular asymmetry distributions obtained within the SM and three different NP scenarios. As expected from SU(3) light-flavor symmetry, we get results close to the ones found in a similar analysis of the (B) over bar -> D-(*()) case. The measurement of the (B) over bar (s) -> D-s(()*())(l (nu) over bar tau) semileptonic decays, which is within reach of present experiments, could then be of relevance in helping to establish or rule out LFUV in CC b -> c transitions.", optnote="WOS:001152794800001", optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=5922), last updated on Sun, 11 Feb 2024 18:11:42 +0000", issn="1029-8479", doi="10.1007/JHEP01(2024)163", opturl="https://arxiv.org/abs/2304.00250", opturl="https://doi.org/10.1007/JHEP01(2024)163", language="English" }