2026/07/19 by Sang-Ho Kim, Myung-Ki Cheoun
#nucl-th #hep-ph
We investigate the reaction mechanism of K-p → ϕΣ0 within a hybrid Regge approach based on effective Lagrangians. The nonresonant background includes Reggeized t-channel K and K^* exchanges, together with ground-state Σ and nucleon exchanges in the s and u channels, respectively. To describe the structures observed at 3.0 \leqslant P\rm Lab \leqslant 4.5 GeV, we include the high-mass Σ(2620) and Σ(3000) resonances and examine the spin-parity assignments JP = 1/2^±, 3/2^±, and 5/2^±. The K^*-Reggeon exchange dominates the forward-angle cross sections, whereas the smaller K-Reggeon contribution is important for the total cross section at low energies and for the spin-density matrix elements. The nonresonant background alone is not sufficient to reproduce the local structures in the total cross section or the differential cross sections at large -t'. Including the two resonances, particularly the Σ(3000), substantially improves the agreement with the available data. The JP=5/2- assignment for the Σ(3000) provides a reasonable overall description, although the present data do not permit a definitive determination.