The pp → K + nΣ + reaction near threshold
نویسنده
چکیده
Inclusive K+ production in proton-proton collisions has been measured at a beam energy of 2.16GeV using the COSY-ANKE magnetic spectrometer. The resulting spectrum, as well as those corresponding to K+p and K+π+ correlated pairs, can all be well described using consistent values of the total cross sections for the pp → K+pΛ, pp → K+pΣ0, and pp → K+nΣ+ reactions. While the resulting values for Λ and Σ0 production are in good agreement with world data, our value for the total Σ+ production cross section, σ(pp → K+nΣ+) = (2.5 ± 0.6stat ± 0.4syst)μb at an excess energy of ε = 129MeV, could only be reconciled with other recently published data if there were a highly unusual near–threshold behaviour.
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Near threshold Λ and Σ production in pp collisions
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