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DOE OSTI · 1960176

Exclusive $|V_{ub}|$ determinations using Padé Approximants

Gonzàlez Solísde la Fuente, Sergi·Masjuan, Pere·Rojas, Camilo
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Abstract

We determine the CKM parameter |V ub | from the exclusive semileptonic decays B→πℓν ℓ and B s →Kℓν ℓ , employing Lattice QCD theoretical information on the form factors in combination with experimental measurements of the differential branching ratio distributions. Using Pad\'{e} approximants to the participating form factors we obtain |V ub |=3.86(11)x10 -3 and |V ub |=3.58(9)x10 -3 from the analyses of the individual decay channels, respectively, and |V ub |=3.68(5)x10 -3 from a simultaneous analysis of both decays. Our results highlight the importance of the decay B s →Kμν μ in complementing the traditional B→πℓν ℓ one in the exclusive determination of |V ub | , and strengthens the case for precise measurements of the differential B s →Kℓν ℓ decay rate with a finer resolution of the q 2 bins, as it would definitely allow achieving more conclusive results for |V ub | .

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS74 ATOMIC AND MOLECULAR PHYSICS

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Gonzàlez Solísde la Fuente, Sergi, Masjuan, Pere, Rojas, Camilo. 2023-01-13. Exclusive $|V_{ub}|$ determinations using Padé Approximants. https://doi.org/10.22323/1.411.0064

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