Study Of The Tensor Mesons Within The Framework Of Resonance Chiral Theory

Quantum Chromodynamics(QCD),in which quarks and gluons are two basic degrees of freedom,is the basic theory to describe the strong interaction.However,it is highly nonperturbative in the low energy region and cannot be analytically solved from the first principles at present.In order to describe the interaction of hadrons in the low energy region,the chiral perturbation theory is constituted based on the chiral symmetry of QCD.As an effective theory of quantum QCD,chiral perturbation theory takes π,K,η mesons as its degrees of freedom.In the variant extentions,heavier η’ meson and f2(1270),a2(1320),f’2(1525),K2*(1430)mesons discussed in this thesis can be added as new degrees of freedom.The main content of this thesis is to discuss tensor mesons based on resonance chiral theory.This thesis is into three parts:the first part is to study the masses of the four tensor resonancesf2(1270),a2(1320),f’2(1525),K2*(1430),and to discuss the mixing of the f20-f28 two states;in the second part,the decay processes of tensor resonances into two pseudoscalar mesons are studied by using chiral effective Lagrangian,and the mixing f20-f28 is further discussed and compared with the results in the first part;the third part focus on the preliminary calculation of the tensor resonance contribution in meson-meson scattering by using Feynman rules and propagators obtained in second part.