The cross section for ee+ e- → π+ π- J/ψ between 3.8 and 5.5 GeV is measured with a 967  fb(-1) data sample collected by the Belle detector at or near the Υ(nS) (n = 1,2,…,5) resonances. The Y(4260) state is observed, and its resonance parameters are determined. In addition, an excess of π+ π- J/ψ production around 4 GeV is observed. This feature can be described by a Breit-Wigner parametrization with properties that are consistent with the Y(4008) state that was previously reported by Belle. In a study of Y(4260) → π+ π- J/ψ decays, a structure is observed in the M(π(±)J/ψ) mass spectrum with 5.2σ significance, with mass M = (3894.5 ± 6.6 ± 4.5)  MeV/c2 and width Γ = (63 ± 24 ± 26)  MeV/c2, where the errors are statistical and systematic, respectively. This structure can be interpreted as a new charged charmoniumlike state.

We report the results of a study of the exclusive semileptonic decays B − → π 0 ℓ −ν ℓ ,B 0 → π + ℓ −ν ℓ , B − → ρ 0 ℓ −ν ℓ ,B 0 → ρ + ℓ −ν ℓ and B − → ωℓ −ν ℓ , where ℓ represents an electron or a muon. The events are tagged by fully reconstructing a second B meson in the event in a hadronic decay mode. The measured branching fractions are B(B − → π 0 ℓ −ν ℓ) = (0.80 ± 0.08 ± 0.04) × 10 −4 , B(B 0 → π + ℓ −ν ℓ) = (1.49 ± 0.09 ± 0.07) × 10 −4 , B(B − → ρ 0 ℓ −ν ℓ) = (1.83 ± 0.10 ± 0.10) × 10 −4 , B(B 0 → ρ + ℓ −ν ℓ) = (3.22 ± 0.27 ± 0.24) × 10 −4 , and B(B − → ωℓ −ν ℓ) = (1.07 ± 0.16 ± 0.07) × 10 −4 , where the first error is statistical and the second one is systematic. The obtained branching fractions are inclusive of soft photon emission. We also determine the branching fractions as a function of the 4-momentum transfer squared to the leptonic system q 2 = (p ℓ + p ν) 2 , where p ℓ and p ν are the lepton and neutrino 4-momenta, respectively. Using the pion modes, a recent LCSR calculation, lattice QCD results and a model-independent description of the hadronic form factor, a value of the CKM matrix element |V ub | = (3.52 ± 0.29) × 10 −3 is extracted. For the first time, a charmless state with invariant mass greater than 1 GeV/c 2 , which might be dominated by the decay B − → f 2 ℓ −ν ℓ , is observed. These results are obtained from a 711 fb −1 data sample that contains 772 × 10 6 BB pairs, collected near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e + e − collider.

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Using 13.5 fb Ϫ1 of e ϩ e Ϫ annihilation data collected with the CLEO II detector, we have observed a narrow resonance decaying to D s * ϩ 0 with a mass near 2.46 GeV/c 2. The search for such a state was motivated by the recent discovery by the BaBar Collaboration of a narrow state at 2.32 GeV/c 2 , the D sJ * (2317) ϩ , that decays to D s ϩ 0. Reconstructing the D s ϩ 0 and D s * ϩ 0 final states in CLEO data, we observe peaks in both of the corresponding reconstructed mass difference distributions, ⌬M (D s 0)ϭM (D s 0)ϪM (D s) and ⌬M (D s * 0)ϭM (D s * 0)ϪM (D s *), both of them at values near 350 MeV/c 2. We interpret these peaks as signatures of two distinct states, the D sJ * (2317) ϩ plus a new state, designated as the D sJ (2463) ϩ. Because of the similar ⌬M values, each of these states represents a source of background for the other if photons are lost, ignored or added. A quantitative accounting of these reflections confirms that both states exist. We have measured the mean mass differences ͗⌬M (D s 0)͘ϭ350.0Ϯ1.2 (stat)Ϯ1.0 (syst) MeV/c 2 for the D sJ * (2317) ϩ state, and ͗⌬M (D s * 0)͘ϭ351.2Ϯ1.7 (stat)Ϯ1.0 (syst) MeV/c 2 for the new D sJ (2463) ϩ state. We have also searched, but find no evidence, for decays of the two states via the channels D s * ϩ ␥, D s ϩ ␥, and D s ϩ ϩ Ϫ. The observations of the two states at 2.32 and 2.46 GeV/c 2 , in the D s ϩ 0 and D s * ϩ 0 decay channels, respectively, are consistent with their interpretations as cs mesons with an orbital angular momentum Lϭ1 and spin and parity J P ϭ0 ϩ and 1 ϩ .

We report preliminary results on the analysis of the three-body Υ( 10860) → B Bπ, Υ(10860) → [B B * + c.c.]π and Υ(10860) → B * B * π decays including an observation of the Υ(10860) → Z ± b (10610)π ∓ → [B B * + c.c.] ± π ∓ and Υ(10860) → Z ± b (10650)π ∓ → [B * B * ] ± π ∓ decays as intermediate channels. We measure branching fractions of the three-body decays to be B(Υ(10860) → [B B * + c.c.] ± π ∓ ) = (28.3 ± 2.9 ± 4.6) × 10 −3 and B(Υ(10860) → [B * B * ] ± π ∓ ) = (14.1 ± 1.9 ± 2.4) × 10 −3 and set 90% C.L. upper limit B(Υ(10860) → [B B] ± π ∓ ) < 4.0 × 10 −3 . We also report results on the amplitude analysis of the three-body Υ(10860) → Υ(nS)π + π − , n = 1, 2, 3 decays and the analysis of the internal structure of the three-body Υ(10860) → h b (mP )π + π − , m = 1, 2 decays. The results are based on a 121.4 fb −1 data sample collected with the Belle detector at a center-of-mass energy near the Υ(10860).