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arXiv · 2403.19025

Analysis of data on $B$ decays into two light vector mesons

Roy Aleksan·Luis Oliver
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Abstract

An important experimental effort has been accomplished in recent years in the measurement of rates, polarization and CP observables in $B$ decays into two light vector mesons. On the theoretical side, after a very consistent effort done within the framework of QCD Factorization, the comparison of the theory with the present experimental data has not been updated, to our knowledge. In the present paper we compare this wealth of data to the theory, in tree color-allowed, tree color-suppressed and pure penguin decays, and present predictions for the observables that have not yet been measured in these decays. In our fits we find acceptable values of $\chi^2$ for the branching ratios and for the direct CP asymmetries. However, this is not the case for the longitudinal polarization fractions, essentially due to disagreement between theory and experiment for the modes $B_{d,s}\to K^{*0}\overline{K}^{*0}$ and $B_d \to \rho^+ \rho^-$. Although we rely on previous work by other authors, we summarize the formalism so that the paper is self-contained and its results can be checked.

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Roy Aleksan, Luis Oliver. 2024-03-27. Analysis of data on $B$ decays into two light vector mesons. https://arxiv.org/abs/2403.19025

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