Abstract.
We show that the recently measured asymmetry in helicity-angle spectra of the Λ-hyperons, produced in the reaction pp → K +Λp reaction, and the energy dependence of the total pp → K +Λp cross-section can be explained consistently by the same Λp final-state interaction. Assuming that there is no final-state interaction in the Σ0 p channel, as suggested by the available data for the reaction pp → K +Σ0 p, we can also reproduce the energy dependence of the Λ/Σ0 production ratio and, in particular, the rather large ratio observed near the reaction thresholds. The nominal ratio of the Λ and Σ0 production amplitudes squared, i.e. when disregarding the final-state interaction, turns out to be about 3, which is in line with hyperon production data from proton and nuclear targets available at high energies.
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Sibirtsev, A., Haidenbauer, J., Hammer, H.W. et al. Phenomenology of the Λ/Σproduction ratio in pp collisions. Eur. Phys. J. A 29, 363–367 (2006). https://doi.org/10.1140/epja/i2006-10097-5
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DOI: https://doi.org/10.1140/epja/i2006-10097-5