σ exchange in the one-boson exchange model involving the ground state octet baryons

Based on the one-boson-exchange framework that the σ meson serves as an effective parametrization for the correlated scalar-isoscalar π π interaction, we calculate the coupling constants of the σ to the 1 2 + ground state light baryon octet B by matching the amplitude of B B ¯ → π π → B ¯ B to that of B B ¯ → σ → B ¯ B . The former is calculated using a dispersion relation, supplemented with chiral perturbation theory results for the B B π π couplings and the Muskhelishvili-Omnès representation for the π π rescattering. Explicitly, the coupling constants are obtained as g N N σ = 8.7 − 1.9 + 1.7 , g Σ Σ σ = 3.5 − 1.3 + 1.8 , g Ξ Ξ σ = 2.5 − 1.4 + 1.5 , and g Λ Λ σ = 6.8 − 1.7 + 1.5 . These coupling constants can be used in the one-boson-exchange model calculations of the interaction of light baryons with other hadrons.