PWA Of J/ψ→p(?)K~+K~- In Besiii

In physics,particles that are subject to strong interactions are called hadrons.Baryons are a type of hadron and can be thought of as bound states of three quarks under strong interactions.The study of the baryon spectrum has always been an important part of hadron physics research,and it plays a crucial role in understanding the microscopic structure of hadrons and the long-range interactions of QCD.The Beijing Electron-Positron Collider(BEPC)is a large electron-positron collider designed and built in China,mainly used for physics experiments in the τ-charm energy region.The Beijing Spectrometer(BESⅢ),which operates at the second-generation Beijing Electron-Positron Collider(BEPCⅡ),has collected the world’s largest data sample of J/ψ with high statistics,providing very favorable conditions for searching and studying excited states of baryons.In this paper,we perform a partial-wave analysis study of the J/ψ→ ppK+K-process using approximately 10 billion J/ψ events collected by BESⅢ at a center-of-mass energy of 3.097 GeV in 2009,2012,2018,and 2019.In the partial-wave analysis,resonance states φ,a0(980),f0(980),φ(1680),ρ(1570),f0(2020),f2(1950),∑(1385),Λ(1520),Λ(1380),and Λ(1405)are chosen as the benchmark solutions to describe the data,and significant measurements are made for these resonance states.Furthermore,the inputoutput checks of the partial-wave analysis results show good agreement.Finally,we measure the branching ratios of possible intermediate processes in the J/ψ/ψ→ ppK+K-process,particularly those involving Λ1/2-,such as J/ψ→ Λ(1380)Λ(1380)→ ppK+K-,J/ψ→ Λ(1405)A(1405)→ ppK+K-,and J/ψ→ Λ(1380)Λ(1405)+c.c→ ppK+K-,providing experimental evidence for the study of Λ1/2-.In addition,we also measure the branching ratio of the J/ψ→ ppK+K-process,which is(1.01±0.01± 0.05)× 10-4.