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arXiv · 0804.4412

Angular Distributions in the Decays B -> K* l+l-

The BABAR Collaboration·B. Aubert
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Abstract

We use a sample of 384 million BBbar events collected with the Babar detector at the PEP-II e+e- collider to study angular distributions in the rare decays B -> K* l+l-, where l+l- is either e+e- or mu+mu-. For low dilepton invariant masses, m(l+l-)<2.5 GeV/c^2, we measure a lepton forward-backward asymmetry AFB=0.24 (+0.18,-0.23) +/- 0.05 and K* longitudinal polarization FL=0.35 +/- 0.16 +/- 0.04$. For m(l+l-)>3.2$ GeV/c^2, we measure AFB=0.76 (+0.52,-0.32) +/- 0.07 FL=0.71 (+0.20,-0.22) +/- 0.04.

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The BABAR Collaboration, B. Aubert. 2009-01-08. Angular Distributions in the Decays B -> K* l+l-. https://doi.org/10.1103/physrevd.79.031102

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