Cross sections for meson–meson nonresonant reactions

Meson–meson nonresonant reactions governed by the quark-interchange mechanism are studied in a potential that is derived from QCD. S-wave elastic phase shifts for I=2 ππ and I=3/2 Kπ scattering are obtained with wave functions determined by the central spin-independent term of the potential. The reactions include inelastic scatterings of two mesons in the ground-state pseudoscalar octet and the ground-state vector nonet. Cross sections for reactions involving π, ρ, K and K* indicate that mesonic interactions in matter consisting of only K and K* can be stronger than mesonic interactions in matter consisting of only π and ρ and the reaction of I=3/2 πK*→ρK is most important among the endothermic nonresonant reactions. By the quark-interchange mechanism we can offer -dependences of ϕ absorption cross sections in collisions with π and ρ and relevant average cross sections what are very small for the reaction of I=1 πϕ→K*K* and remarkably large for the reaction of I=1 ρϕ→K*K*. It is found from the -dependences of cross sections that ρ and K* creation cross sections can be larger than their absorption cross sections, respectively.