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The reaction ?p?K0S+ was measured in the photon energy range from threshold up to 2.6 GeV with the SAPHIR detector at the electron stretcher facility, ELSA, in Bonn. Results are presented on the reaction cross-section and the polarization of the S+ as a function of the kaon production angle in the centre-of-mass system, cosTc.m.K, and the photon energy. The cross-section is lower and varies less with photon energy and kaon production angle than that of ?p?K+S0. The S+ is polarized predominantly at cosTc.m.K ˜ 0. The data presented here are more precise than previous ones obtained with SAPHIR and extend the photon energy range to higher values. They are compared to isobar model calculations. [ABSTRACT FROM AUTHOR]

Branching ratios for the decay of hadrons with large width or near thresholds depend on their definition. We test different definitions and show that rather different branching ratios can be obtained. For wide resonances and for sequential decays with wide intermediate resonances, integration over the spectral functions is mandatory. The tests are performed exploiting the latest solution of the Bonn-Gatchina multi-channel analysis and published values for residues of light scalar mesons. For a resonance overlapping with a threshold, in case its pole lies in a non-adjacent sheet, we show how the total width, needed for the branching ratios, does not correspond to the imaginary part of the pole position. We use the Madrid-Krakow dispersive parameterizations to illustrate this situation with the f 0 (980). [ABSTRACT FROM AUTHOR]

The reaction ?p?K0S+ was measured in the photon energy range from threshold up to 2.6 GeV with the SAPHIR detector at the electron stretcher facility, ELSA, in Bonn. Results are presented on the reaction cross-section and the polarization of the S+ as a function of the kaon production angle in the centre-of-mass system, cosTc.m.K, and the photon energy. The cross-section is lower and varies less with photon energy and kaon production angle than that of ?p?K+S0. The S+ is polarized predominantly at cosTc.m.K ˜ 0. The data presented here are more precise than previous ones obtained with SAPHIR and extend the photon energy range to higher values. They are compared to isobar model calculations. [ABSTRACT FROM AUTHOR]