Future Colliders

Abstract:

We report on the results of a partial-wave analysis of the 3π system produced by baryon exchange in the reaction K^-p→Σ^-π⁺π⁺π^- at 4.2 GeV/c. We confirm the existence of an enhancement in the 1⁺S(ρ{variant}π) wave as previously established from a Dalitz plot analysis of the same data. The phase variation of this wave is found to be consistent with that expected for a resonance and thus the enhancement is identified with A1 production. No clear signal for this state is found in either the reaction K^-p→Σ⁺π⁺π⁺π^-π^- or K^-p→Λπ⁺π^-π⁰. We also find production via baryon exchange of the A2 in all three reactions and the ω and ω^* (1975) in the third reaction. © 1981.

Abstract:

The reactions K^-p → Ξ ^{0 -}(1320)K ^{0 +}, Ξ^-(1320)K⁺(890), Ξ ^{0 -}(1530) K ^{0 -} and Ξ ^{0 -}(1530)K ^{0 +}(890) are studied at 4.2 GeV/c incident momentum. The data come from a high-statistics bubble chamber experiment with a sensitivity of ∼ 133 events/μb. Total anddifferential cross sections are presented. The results are compared to the SU(3)-related processes K⁺p → pK⁺ and K⁺p → pK⁺(890) in the backward hemisphere. In the forward hemisphere "forbidden" peaks are observed and current ideas about them are discussed. © 1981.