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We report on a search for new resonant states in the process gamma gamma --> DD. A candidate C-even charmonium state is observed in the vicinity of 3.93 GeV/c2. The production rate and the angular distribution in the gamma gamma center-of-mass frame suggest that this state is the previously unobserved chi(c2)', the 2(3)P2 charmonium state.

The cross section for e + e − → π + π − ψ(2S) between threshold and √ s = 5.5 GeV is measured using 673 fb −1 of data on and off the Υ(4S) resonance collected with the Belle detector at KEKB. Two resonant structures are observed in the π + π − ψ(2S) invariant mass distribution, one at 4361 ± 9 ± 9 MeV/c 2 with a width of 74 ± 15 ± 10 MeV/c 2 , and another at 4664 ± 11 ± 5 MeV/c 2 with a width of 48 ± 15 ± 3 MeV/c 2 , if the mass spectrum is parameterized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states.

We perform a full amplitude analysis of B 0 → ψ ′ K + π − decays, with ψ ′ → µ + µ − or e + e − , to constrain the spin and parity of the Z(4430) −. The J P = 1 + hypothesis is favored over the 0 − , 1 − , 2 − and 2 + hypotheses at the levels of 3.4σ, 3.7σ, 4.7σ and 5.1σ, respectively. The analysis is based on a 711 fb −1 data sample that contains 772 × 10 6 BB pairs collected at the Υ(4S) resonance by the Belle detector at the asymmetric-energy e + e − collider KEKB.

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