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arXiv · 0710.1907

Cross sections for meson-meson nonresonant reactions

Yu-Qi Li·Xiao-Ming Xu
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Abstract

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 ππand I=3/2 K πscattering 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 pion, rho, 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 pions and rhos and the reaction of I=3/2 πK^* \to ρK is most important among the endothermic nonresonant reactions. By the quark-interchange mechanism we can offer \sqrt s-dependences of phi absorption cross sections in collisions with pion and rho and relevant average cross sections what are very small for the reaction of I=1 πϕ\to K^* K^* and remarkably large for the reaction of I=1 ρϕ\to K^* K^*. It is found from the \sqrt s-dependences of cross sections that rho and K^* creation cross sections can be larger than their absorption cross sections, respectively.

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Yu-Qi Li, Xiao-Ming Xu. 2007-10-10. Cross sections for meson-meson nonresonant reactions. https://doi.org/10.1016/j.nuclphysa.2007.08.009

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