A closer look at the extraction of |Vub| from B → πℓν

Abstract

Abstract To extract the Cabibbo-Kobayashi-Maskawa (CKM) matrix element |V ub |, we have re-analyzed all the available inputs (data and theory) on the B → πℓν decays including the newly available inputs on the form-factors from light cone sum rule (LCSR) approach. We have reproduced and compared the results with the procedure taken up by the Heavy Flavor Averaging Group (HFLAV), while commenting on the effect of outliers on the fits. After removing the outliers and creating a comparable group of data-sets, we mention a few scenarios in the extraction of |V ub |. In all those scenarios, the extracted values of |V ub | are higher than that obtained by HFLAV. Our best results for |V ub | exc. are (3.94 ± 0.14) × 10 −3 and 3.93 − 0.15 + 0.14 $$ \left({3.93}_{-0.15}^{+0.14}\right) $$ × 10 −3 in frequentist and Bayesian approaches, respectively, which are consistent with that extracted from inclusive decays |V ub | inc. within 1 σ confidence interval.

Keywords

• Heavy Quark Physics
• Quark Masses and SM Parameters