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We update the standard model (SM) predictions of $R(D^*)$ using the latest results on the decay distributions in $B to D^* ell u_{ell}$ ($ell = mu, e$) by Belle collaboration, while extracting $|V_{cb}|$ at the same time. Depending on the inputs used in the analysis, we define various fit scenarios. Although the central values of the predicted $R(D^*)$ in all the scenarios have reduced from its earlier predictions in 2017, the results are consistent with each other within the uncertainties. In this analysis, our prediction of $R(D^*)$ is consistent with the respective world average at $sim 3sigma$. We have also predicted several angular observables associated with $B to D^* tau u_{tau}$ decays. We note that the predicted $F_L(D^*)$ is consistent with the corresponding measurement at 2$sigma$. Utilizing these new results, we fit the Wilson coefficients appearing beyond the standard model of particle physics (BSM). To see the trend of SM predictions, we have utilized the recently published preliminary results on the form-factors at non-zero recoil by the lattice groups like Fermilab-MILC and JLQCD and predicted the observables in $B to D^* ell u_{ell}$, and $B to D^* tau u_{tau}$ decays.
We extract $|V_{cb}|$ from the available data in the decay $B to D^{(*)}ell u_{ell}$. Our analysis uses the $q^2(w)$ binned differential decay rates in different subsamples of $Bto Dell u_ell$ ($ell = e, mu$), while for the decay $Bto D^*ell u_ell$,
The Cabibbo-Kobayashi-Maskawa (CKM) matrix element $vert V_{cb}vert$ is extracted from exclusive semileptonic $B to D^{(*)}$ decays adopting a novel unitarity-based approach which allows to determine in a full non-perturbative way the relevant hadron
After improving the knowledge about residua of the semileptonic form factor at its first two poles we show that $f_+^{Dpi}(q^2)$ is not saturated when compared with the experimental data. To fill the difference we approximate the rest of discontinuit
Besides being important to determine Standard Model parameters such as the CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$, semileptonic $B$ decays seem also promising to reveal new physics (NP) phenomena, in particular in connection with the possibili
We present nearly final results from our analysis of the form factors for $Bto D^astell u$ decay at nonzero recoil. Our analysis includes 15 MILC asqtad ensembles with $N_f=2+1$ flavors of sea quarks and lattice spacings ranging from $aapprox0.15$ fm