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arXiv · 2404.17440

Disentangling left and right-handed neutrino effects in $B\rightarrow K^{(*)}\nu\nu$

L. P. S. Leal·S. Rosauro-Alcaraz
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Abstract

The first observation of $\mathcal{B}\left(B^+\rightarrow K^+\nu\nu\right)$ by the Belle II experiment lies almost $3\sigma$ away from the Standard Model expectation. In this letter we study this result in the SMEFT, extended by a light right-handed neutrino. We explore the correlations between the measured decay rate and other observables, such as $\mathcal{B}\left(B\rightarrow K^*\nu\nu\right)$ and $F_L\left(B\rightarrow K^*\nu\nu\right)$, showing that they could disentangle among scenarios involving left-handed neutrinos and those with the right-handed ones. Furthermore, we find that the high-$p_T$ tails of Drell-Yan processes studied at LHC provide important constraints that help us exclude some of the scenarios consistent with the Belle II result.

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L. P. S. Leal, S. Rosauro-Alcaraz. 2024-04-26. Disentangling left and right-handed neutrino effects in $B\rightarrow K^{(*)}\nu\nu$. https://doi.org/10.1140/epjc%2Fs10052-024-13104-x

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