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arXiv · 0807.4076

Exclusive b \to s (d) ll Decays

G. Eigen
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Abstract

New BABAR measurements are presented for the exclusive rare decays B -> K(*) l+ l- including branching fractions, isospin asymmetries, direct CP violation, and lepton flavor universality for dilepton masses below and above the J/psi resonance. Unexpectedly large isospin asymmetries are observed in both K l+l- and K* l+ l- decays. For the combined K l+l- and K* l+l- data a 3.9 sigma significant deviation from the SM prediction is found. Furthermore, recent BABAR results from an angular analysis in B -> K* l+l- are reported in which both the K* longitudinal polarization and the lepton forward-backward asymmetry are measured for dilepton masses below and above the J/psi resonance. Finally, results of recent searches for B -> pi l+l-$ from Belle and B -> K(*) nu anti nu$ from BABAR are summarized.

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G. Eigen. 2008-07-25. Exclusive b \to s (d) ll Decays. https://arxiv.org/abs/0807.4076

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