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We study B --> K(*)l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K* polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 = M(ll)(2)c2. The fitted A(FB) spectrum exceeds the standard model expectation by 2.7 standard deviations. The measured branching fractions are B(B --> K*l+l-) = (10.7(-1.0)(+1.1) +/- 0.9) x 10(-7) and B(B --> Kl+l-) = (4.8(-0.4)(+0.5) +/- 0.3) x 10(-7), where the first errors are statistical and the second are systematic, with the muon to electron ratios R(K*) = 0.83 +/- 0.17 +/- 0.08 and R(K) = 1.03 +/- 0.19 +/- 0.06.

We report a measurement of the process γγ * → π 0 with a 759 fb −1 data sample recorded with the Belle detector at the KEKB asymmetric-energy e + e − collider. The pion transition form factor, F (Q 2 ), is measured for the kinematical region 4 GeVGeV 2 , where −Q 2 is the invariant mass squared of a virtual photon. The measured values of Q 2 |F (Q 2 )| agree well with the previous measurements below Q 2 ≃ 9 GeV 2 but do not exhibit the rapid growth in the higher Q 2 region seen in another recent measurement, which exceeds the asymptotic QCD expectation by as much as 50%.

Bounds on the width, mass difference and other properties of X(3872) → π + π − J/ψ decays

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