R. Bilger

Thepp→ppπ+π−reaction studied in the low-energy tail of the Roper resonance

Exclusive measurements of the p p ->p p pi+ pi- reaction have been carried out at Tp = 775 MeV at CELSIUS using the PROMICE/WASA setup. Together with data obtained at lower energy they point to a dominance of the Roper excitation in this process. From the observed interference of its decay routes N* ->N sigma and N* ->Delta pi ->N sigma their energy-dependent relative branching ratio is determined.

Higher partial waves in p p ---> p p eta near threshold

Abstract Exclusive measurements of the production of η -mesons in the pp → ppη reaction have been carried out at excess energies of 16 and 37 MeV above threshold. The deviations from phase space are dominated by the proton-proton final state interaction and this influences particularly the energy distribution of the η -meson. However, evidence is also presented at the higher energy for the existence of an anisotropy in the angular distributions of the η -meson and also of the final proton-proton pair, probably to be associated with D -waves in this system interfering with the dominant S -wave term. The sign of the η angular anisotropy suggests that ρ -exchange is important for this reaction.

On the production of \pi^{+}_{} \pi^{+}_{} pairs in pp collisions at 0.8 GeV

Data accumulated recently for the exclusive measurement of the pp

Spectator tagging in quasi-free proton–neutron interactions in deuterium using an internal cluster-jet target at a storage ring

\rightarrow

Pionic D-wave effects in pp→ppπ0 near threshold

pp

Search for the hypothetical π → μx decay

\pi^{+}_{}

Inclusive measurements of pionic double charge exchange on 3He at low energies

\pi^{-}_{}

Pionic double charge exchange on 93Nb at low energies

reaction at a beam energy of 0.793GeV using the COSY-TOF spectrometer have been analyzed with respect to possible events from the pp

Evidence for a dibaryon resonance in the pionic double charge exchange

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