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Background: There is a renewed experimental interest in antiproton-proton scattering with an intense, possibly polarized antiproton beam. On the theoretical side, significant progress has been made in the understanding of the nuclear force from chiral effective field theory.Purpose: We provide a high-quality model-independent description of the available low-energy antiproton-proton scattering data. Method: We perform a new energy-dependent partial-wave analysis of all antiproton-proton elastic ((p) over barp -> (p) over barp) and charge-exchange ((p) over barp -> (n) over barn) scattering data below 925 MeV/c antiproton laboratory momentum. The Schrodinger equation is solved for the coupled (p) over barp and (n) over barn channels. The relevant long-range parts of the electromagnetic and the one-and two-pion exchange interactions are included exactly. The short-range interactions, including the coupling to the mesonic annihilation channels, are parametrized by a complex boundary condition at a radius of r = 1.2 fm.Results: The updated database, which includes significantly more high-quality charge-exchange data, contains 3749 scattering data. The fit gives chi(2)(min)/N-df = 1.048, where N-df = 3578 is the number of degrees of freedom. We discuss the description of the experimental data and we present the antiproton-proton phase-shift parameters.Conclusions: Chiral effective field theory provides an excellent long-range antinucleon-nucleon interaction. The results of the PWA should serve as the starting point for future theoretical and experimental investigations of low-energy antiproton-proton scattering.

We discuss the possibility of using electroproduction of J/psi as a probe of gluon Sivers function by measuring single spin asymmetry (SSA) in experiments with transversely polarized protons and electron beams. We estimate SSA for JLab, HERMES, COMPASS, and eRHIC energies using the color evaporation model of charmonium production and find asymmetry up to 25% for certain choices of model parameters which have been used earlier for estimating SSA in the SIDIS and Drell-Yan processes.

In view of the persisting misunderstandings about the determination of the pion-nucleon coupling constants in the Nijmegen multienergy partial-wave analyses of pp, np, and ppBAR scattering data, we present additional information which may clarify several points of discussion. We comment on several recent papers addressing the issue of the pion-nucleon coupling constant and criticizing the Nijmegen analyses.

The Mg-24(d,He-2)Na-24 and the C-12(d,He-2)B-12 charge-exchange reactions have been studied at an incident energy of 170 MeV. The two protons in the S-1(0)(pp) state (indicated as He-2) were both momentum analyzed and detected by the same spectrometer and detector. Background-free He-2 spectra with a resolution of about 150 keV (full width at half maximum) have been obtained allowing identification of many levels in the residual nucleus with high precision. It is found that the (d,He-2) reaction at 0degrees is largely governed by the Gamow-Teller (GT) transition operator for the beta(+) direction, which makes the reaction selective for isovector 1(+) transitions. In the case of Mg-24, the reaction is compared with (p,n) reaction data in which the same levels in the analog nucleus Al-24 are populated. Angular distributions of cross sections for the (d,He-2) reaction are presented and compared with distorted-wave Born approximation calculations. GT matrix elements are deduced. A level-by-level comparison with shell-model calculations using the universal s-d interaction has been performed. Comparison with (p,p(')) data yields a level scheme for the A=24 isospin triplet.