B -> K(*) l+ l- @ Low Recoil and Physics Implications

Gudrun Hiller

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arXiv · 1305.6456

B -> K(*) l+ l- @ Low Recoil and Physics Implications

Gudrun Hiller

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Abstract

This talk covers recent theoretical progress in exclusive semileptonic rare B-decays at low hadronic recoil. The efficient parametric suppression of the 1/mb corrections in this region provides opportunities to probe the Standard Model and beyond at precision level. Notably, angular analysis allows to simultaneously access electroweak flavor physics and hadronic matrix elements, the latter of which constitute the leading source of theoretical uncertainty. Ratios of B ->K* form factors can already be extracted from present data. A comparison with existing theoretical determinations by lattice QCD and light cone sum rules gives a consistent picture over the whole kinematic range. In the future improved analyses will advance our understanding of non-perturbative methods for QCD and of |Delta B|=1 transitions.

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Gudrun Hiller. 2013-05-28. B -> K(*) l+ l- @ Low Recoil and Physics Implications. https://arxiv.org/abs/1305.6456

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