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There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESIII and B factories, and the observation of an intriguing proton-antiproton threshold enhancement and the possibly related X(1835) meson state at BESIII, as well as the threshold measurements of charm mesons and charm baryons. We present a detailed survey of the important topics in tau-charm physics and hadron physics that can be further explored at BESIII during the remaining operation period of BEPCII. This survey will help in the optimization of the data-taking plan over the coming years, and provides physics motivation for the possible upgrade of BEPCII to higher luminosity.

We report on an exclusive and kinematically complete high-statistics measurement of the basic doublepionic fusion reaction pn ! d 0 0 over the full energy region of the ABC effect, a pronounced low-mass enhancement in the -invariant mass spectrum. The measurements, which cover also the transition region to the conventional t-channel ÁÁ process, were performed with the upgraded WASA detector setup at COSY. The data reveal the Abashian-Booth-Crowe effect to be uniquely correlated with a Lorentzian energy dependence in the integral cross section. The observables are consistent with a narrow resonance PRL

Exclusive and kinematically complete high-statistics measurements of quasifree polarized np scattering have been performed in the energy region of the narrow resonance-like structure d * with 2 I(J P ) = 0(3 + ), M ≈ 2380 MeV and Γ ≈ 70 MeV observed recently in the double-pionic fusion channels pn → dπ 0 π 0 and pn → dπ + π − . The experiment was carried out with the WASA detector setup at COSY having a polarized deuteron beam impinged on the hydrogen pellet target and utilizing the quasifree process dp → np + pspectator. This allowed the np analyzing power, Ay, to be measured over a broad angular range. The obtained Ay angular distributions deviate systematically from the current SAID SP07 NN partial-wave solution. Incorporating the new Ay data into the SAID analysis produces a pole in the 3 D3 − 3 G3 waves in support of the d * resonance hypothesis.

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