Study of the reaction p̄p → \̄gLΛ at 1.546 and 1.695 GeV/c

doi:10.1016/0375-9474(91)90434-8

Nuclear Physics A

Volume 526, Issues 3–4, 6–13 May 1991, Pages 575-601

https://doi.org/10.1016/0375-9474(91)90434-8 Get rights and content

Abstract

The PS185 experiment at the CERN Low Energy Antiproton Ring (LEAR) has studied the reaction $p ̄ p → \ ̄ gLΛ$ at several momenta. In this paper results from two runs with high statistics at 1.546 GeV/c and 1.695 GeV/c are described. Based on 4063 and 11362 analysed events, respectively, differential and integrated cross sections, polarizations and spin correlations are presented. The singlet fraction, extracted from the spin correlations, is consistent with zero at both momenta, showing that the $\ ̄ gLΛ$ pairs are produced in a pure triplet state. A comparison of the decay asymmetry parameters of Λ and $\ ̄ gL$ reduces the upper limits for the violation of the CP invariance for this system.

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¹: Present addresses: Institut für Kernphysik der KFA, D-5170 Jülich, Germany.

^†: Deceased.

²: Present addresses: CERN, CH-1211 Geneva 23, Switzerland.

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Nuclear Physics A

Abstract

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Exploring the potential of antihyperons in nuclei with antiprotons

Exploring the potential of antilambdas in nuclei with antiprotons

ΛΛ¯ final-state interaction in the reactions e<sup>+</sup>e<sup>-</sup>→ ϕΛΛ¯ and e<sup>+</sup>e<sup>-</sup>→ ηΛΛ¯