Strangeness production process pp -> nK(+)Sigma(+) within resonance model

Abstract

We explore production mechanism and final state interaction in the pp -> nK(+)Sigma(+) channel based on the inconsistent experimental data published respectively by COSY-11 and COSY-ANKE. The scattering parameter a > 0 for n Sigma(+) interaction is favoured by large near-threshold cross section within a nonrelativistic parametrization investigation, and a strong n Sigma(+) interaction comparable to pp interaction is also indicated. Based on this analysis we calculate the contribution from resonance Delta*(1920) through pi(+) exchange within resonance model, and the numerical result suggests a rather small near-threshold total cross section, which is consistent with the COSY-ANKE data. With an additional sub-threshold resonance Delta*(1620), the model gives a much better description to the rather large near-threshold total cross section published by COSY-11SupportedbytheKnowledgeInnovationProjectofChineseAcademyofSciencesunderGrantNosKJCX3-SYW-N2and KJCX2-SW-N16,andtheNationalNaturalScienceFoundationofChinaunderGrantNos10435080,10575123,and10710172