00 40 22 v 1 1 0 A pr 2 00 0 1 On the Λ to Σ 0 ratio from proton - proton collisions ∗
نویسنده
چکیده
We compare the recent COSY data on the total pp→pΛK and pp→pΣK cross sections with the predictions from two boson exchange models that either are based solely on π and K exchange or include π, η and ρ exchange as well as the virtual excitation of intermediate baryon resonances. Both models are found to reproduce the data after the inclusion of final state hyperon-nucleon interactions. Thus, within the experimental uncertainties, both models also roughly reproduce the strong dependence of the Λ to Σ ratio as a function of the excess energy near threshold, as well as at higher energies.
منابع مشابه
0 00 40 22 v 2 5 M ay 2 00 0 1 On the Λ to Σ 0 ratio from proton - proton collisions ∗
We compare the recent COSY data on the total pp→pΛK and pp→pΣK cross sections with the predictions from two boson exchange models that either are based solely on π and K exchange or include π, η and ρ exchange as well as the virtual excitation of intermediate baryon resonances. Both models are found to reproduce the data after the inclusion of final state hyperon-nucleon interactions. Thus, wit...
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