Insisting on the role of experimental data: the pseudoscalar-pole piece to the $(g_\mu-2)$ and the $|V_{ub}|$ from $B \to \pi \ell \nu_{\ell}$ differential branching ratio

Sergi Gonzàlez-Solís; Pere Masjuan; Pablo Sanchez-Puertas

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arXiv · 1802.05017

Insisting on the role of experimental data: the pseudoscalar-pole piece to the $(g_\mu-2)$ and the $|V_{ub}|$ from $B \to \pi \ell \nu_{\ell}$ differential branching ratio

Sergi Gonzàlez-Solís·Pere Masjuan·Pablo Sanchez-Puertas

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Abstract

We employ a mathematical framework based on rational approximants in order to calculate meson form factors. The method profits from unitary, is systematic and data based, and is able to ascribe a systematic uncertainty which provides for the desired model independence. Two examples are discussed: the transition form factor entering the pseudoscalar-pole piece of the hadronic light-by-light contribution to the anomalous magnetic moment of the muon, and the $B \to \pi$ form factor participating the $B\to\pi\ell\nu_{\ell}$ differential branching ratios which allows to determine the $|V_{ub}|$ CKM parameter.

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Sergi Gonzàlez-Solís, Pere Masjuan, Pablo Sanchez-Puertas. 2018-02-14. Insisting on the role of experimental data: the pseudoscalar-pole piece to the $(g_\mu-2)$ and the $|V_{ub}|$ from $B \to \pi \ell \nu_{\ell}$ differential branching ratio. https://arxiv.org/abs/1802.05017

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