TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhysProc.1.013
TI  - Probing lepton universality with (semi)-leptonic B decays
PY  - 2019/02/19
UR  - https://www.scipost.org/SciPostPhysProc.1.013
JF  - SciPost Physics Proceedings
JA  - SciPost Phys. Proc.
VL  - 
IS  - 1
SP  - 013
A1  - Banelli, Giovanni
AU  - Fleischer, Robert
AU  - Jaarsma, Ruben
AU  - Tetlalmatzi-Xolocotzi, Gilberto
AB  - The most recent measurements of the observables $R_{D^{(*)}}$ are in tension with the Standard Model offering hints of New Physics in $b\rightarrow c \ell \bar{\nu}_{\ell}$ transitions. Motivated by these results, in this work we present an analysis on their $b\rightarrow u \ell \bar{\nu}_{\ell}$ counterparts (for $\ell=e, ~\mu, ~\tau$). Our study has three main objectives. Firstly, using ratios of branching fractions, we assess the effects of beyond the Standard Model scalar and pseudoscalar particles in leptonic and semileptonic $B$ decays ($B^-\rightarrow \ell^- \bar{\nu}_{\ell}$, $\bar{B}\rightarrow \pi \ell \bar{\nu}_{\ell}$ and $\bar{B}\rightarrow \rho \ell \bar{\nu}_{\ell}$). Here a key role is played by the leptonic $B$ processes, which are highly sensitive to new pseudoscalar interactions. In particular, we take advantage of the most recent measurement of the branching fraction of the channel $B^-\rightarrow \mu^-\bar{\nu}_{\mu}$ by the Belle collaboration. Secondly, we extract the CKM matrix element $|V_{ub}|$ while accounting simultaneously for New Physics contributions. Finally, we provide predictions for the branching fractions of yet unmeasured leptonic and semileptonic $B$ decays.
ER  -

@Article{10.21468/SciPostPhysProc.1.013,
	title={{Probing lepton universality with (semi)-leptonic B decays}},
	author={Giovanni Banelli and Robert Fleischer and Ruben Jaarsma and Gilberto Tetlalmatzi-Xolocotzi},
	journal={SciPost Phys. Proc.},
	pages={013},
	year={2019},
	publisher={SciPost},
	doi={10.21468/SciPostPhysProc.1.013},
	url={https://scipost.org/10.21468/SciPostPhysProc.1.013},
}